Middlesex Water (MSEX) 10-K25 Feb 212020 FY Annual reportFinancial data

Company Profile

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2020	Feb. 25, 2021	Jun. 30, 2020
Document And Entity Information [Abstract]
Document Type	10-K
Entity Central Index Key	0000066004
Document Period End Date	Dec. 31, 2020
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2020
Amendment Flag	false
Document Annual Report	true
Document Transition Report	false
Entity File Number	0-422
Entity Registrant Name	MIDDLESEX WATER COMPANY
Entity Incorporation State Country Code	NJ
Entity Tax Identification Number	22-1114430
Entity Address, Address Line One	485C Route 1 South
Entity Address, Address Line Two	Suite 400
Entity Address, City or Town	Iselin
Entity Address, State or Province	NJ
Entity Address, Postal Zip Code	08830
City Area Code	732
Local Phone Number	634-1500
Title of 12(b) Security	Common Stock, No Par Value
Trading Symbol	MSEX
Name of Exchange on which Security is Registered	NASDAQ
Current Fiscal Year End Date	--12-31
Entity a Well-known Seasoned Issuer	Yes
Entity a Voluntary Filer	No
Entity Reporting Status Current	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 1,152,416,738
Entity Common Stock, Shares Outstanding		17,474,598
Documents Incorporated By Reference Text Block	Proxy Statement to be filed in connection with the Registrant’s Annual Meeting of Stockholders to be held on May 25, 2021, which will be filed with the Securities and Exchange Commission within 120 days of the end of our 2020 fiscal year, is incorporated by reference into Part III of this Annual Report on Form 10-K to the extent described herein.

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	12 Months Ended
CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Statement [Abstract]
Operating Revenues	$ 141,592	$ 134,598	$ 138,077
Operating Expenses:
Operations and Maintenance	70,796	67,980	71,570
Depreciation	18,472	16,716	15,037
Other Taxes	14,904	14,382	14,328
Total Operating Expenses	104,172	99,078	100,935
Operating Income	37,420	35,520	37,142
Other Income (Expense):
Allowance for Funds Used During Construction	4,016	3,146	1,362
Other Income (Expense), net	363	(654)	1,630
Total Other Income, net	4,379	2,492	2,992
Interest Charges	7,493	7,264	6,758
Income before Income Taxes	34,306	30,748	33,376
Income Taxes	(4,119)	(3,140)	924
Net Income	38,425	33,888	32,452
Preferred Stock Dividend Requirements	120	132	144
Earnings Applicable to Common Stock	$ 38,305	$ 33,756	$ 32,308
Earnings per share of Common Stock:
Basic	$ 2.19	$ 2.02	$ 1.97
Diluted	$ 2.18	$ 2.01	$ 1.96
Average Number of Common Shares Outstanding :
Basic	17,459	16,685	16,384
Diluted	17,574	16,829	16,540

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
UTILITY PLANT:
Water Production	$ 168,080	$ 160,870
Transmission and Distribution	648,763	556,517
General	85,056	83,043
Construction Work in Progress	80,055	75,520
TOTAL	981,954	875,950
Less Accumulated Depreciation	185,356	170,220
UTILITY PLANT - NET	796,598	705,730
CURRENT ASSETS:
Cash and Cash Equivalents	4,491	2,230
Accounts Receivable, net	14,569	11,908
Unbilled Revenues	7,065	7,183
Materials and Supplies (at average cost)	5,112	5,445
Prepayments	2,886	2,367
TOTAL CURRENT ASSETS	34,123	29,133
Operating Lease Right of Use Asset	5,209	5,944
Preliminary Survey and Investigation Charges	5,192	2,054
Regulatory Assets	118,144	110,479
Restricted Cash	5,913	44,269
Non-utility Assets - Net	11,207	10,370
Other	84	1,899
TOTAL OTHER ASSETS	145,749	175,015
TOTAL ASSETS	976,470	909,878
CAPITALIZATION:
Common Stock, No Par Value	217,451	215,125
Retained Earnings	128,757	108,667
TOTAL COMMON EQUITY	346,208	323,792
Preferred Stock	2,084	2,084
Long-term Debt	273,244	230,777
TOTAL CAPITALIZATION	621,536	556,653
CURRENT LIABILITIES:
Current Portion of Long-term Debt	7,255	7,178
Notes Payable	2,000	20,000
Accounts Payable	30,443	23,306
Accrued Taxes	10,138	7,635
Accrued Interest	2,137	2,031
Unearned Revenues and Advanced Service Fees	1,255	1,211
Other	3,620	3,620
TOTAL CURRENT LIABILITIES	56,848	64,981
COMMITMENTS AND CONTINGENT LIABILITIES (Note 4)
OTHER LIABILITIES:
Customer Advances for Construction	23,404	23,905
Lease Obligations	5,042	5,732
Accumulated Deferred Income Taxes	61,297	54,408
Employee Benefit Plans	34,426	34,671
Regulatory Liabilities	60,792	69,152
Other	1,135	2,546
TOTAL OTHER LIABILITIES	186,096	190,414
CONTRIBUTIONS IN AID OF CONSTRUCTION	111,990	97,830
TOTAL CAPITALIZATION AND LIABILITIES	$ 976,470	$ 909,878

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income	$ 38,425	$ 33,888	$ 32,452
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities:
Depreciation and Amortization	20,838	17,232	15,780
Provision for Deferred Income Taxes	(13,490)	(11,719)	(8,724)
Equity Portion of Allowance for Funds Used During Construction (AFUDC)	(2,503)	(1,997)	(919)
Cash Surrender Value of Life Insurance	(391)	(252)	27
Stock Compensation Expense	1,096	637	1,084
Changes in Assets and Liabilities:
Accounts Receivable	(2,661)	(146)	(977)
Unbilled Revenues	118	110	(294)
Materials & Supplies	333	(34)	(1,293)
Prepayments	(519)	277	(236)
Accounts Payable	7,137	3,981	5,396
Accrued Taxes	2,503	(6,595)	2,812
Accrued Interest	106	742	196
Employee Benefit Plans	(1,377)	(1,112)	(2,114)
Unearned Revenue & Advanced Service Fees	44	175	85
Other Assets and Liabilities	3,696	866	2,589
NET CASH PROVIDED BY OPERATING ACTIVITIES	53,355	36,053	45,864
CASH FLOWS FROM INVESTING ACTIVITIES:
Utility Plant Expenditures, Including AFUDC of $1,513 in 2020, $1,149 in 2019 and $443 in 2018	(105,619)	(89,125)	(72,094)
NET CASH USED IN INVESTING ACTIVITIES	(105,619)	(89,125)	(72,094)
CASH FLOWS FROM FINANCING ACTIVITIES:
Redemption of Long-term Debt	(7,472)	(7,343)	(7,024)
Proceeds from Issuance of Long-term Debt	50,316	78,967	22,076
Proceeds from Premium Issuance of Long-term Debt		7,083
Net Short-term Bank Borrowings	(18,000)	(28,500)	20,500
Deferred Debt Issuance Expense	(148)	(769)	(880)
Common Stock Issuance Expense	(37)	(357)
Proceeds from Issuance of Common Stock	1,230	56,784	1,150
Payment of Common Dividends	(18,178)	(16,165)	(14,930)
Payment of Preferred Dividends	(120)	(132)	(144)
Construction Advances and Contributions-Net	8,578	4,342	4,746
NET CASH PROVIDED BY FINANCING ACTIVITIES	16,169	93,910	25,494
NET CHANGES IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	(36,095)	40,838	(736)
CASH, CASH EQUIVALENTS AND RESTRICTED CASH AT BEGINNING OF PERIOD	46,499	5,661	6,397
CASH, CASH EQUIVALENTS AND RESTRICTED CASH AT END OF PERIOD	10,404	46,499	5,661
SUPPLEMENTAL DISCLOSURE OF NON-CASH ACTIVITY:
Utility Plant received as Construction Advances and Contributions	5,080	7,770	3,835
Long-term Debt Deobligation	258	130
Cash Paid During the Year for:
Interest	7,644	6,938	6,113
Interest Capitalized	1,513	1,149	443
Income Taxes	$ 2,509	$ 10,339	$ 4,689

CONSOLIDATED STATEMENTS OF CA_2

CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Cash Flows [Abstract]
Allowance for funds used during construction	$ 1,513	$ 1,149	$ 443

CONSOLIDATED STATEMENTS OF CAPI

CONSOLIDATED STATEMENTS OF CAPITAL STOCK AND LONG-TERM DEBT - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Common Stock, No Par Value	$ 217,451	$ 215,125
Retained Earnings	128,757	108,667
TOTAL COMMON EQUITY	346,208	323,792
TOTAL PREFERRED STOCK	2,084	2,084
SUBTOTAL LONG-TERM DEBT	277,241	234,397
Add: Premium on Issuance of Long-term Debt	7,669	8,064
Less: Unamortized Debt Expense	(4,411)	(4,506)
Less: Current Portion of Long-term Debt	(7,255)	(7,178)
TOTAL LONG-TERM DEBT	273,244	230,777
Convertible Preferred Stock $7.00 Series
SUBTOTAL LONG-TERM DEBT	1,005	1,005
Nonredeemable Preferred Stock $7.00 Series
SUBTOTAL LONG-TERM DEBT	79	79
Nonredeemable Preferred Stock $4.75 Series [Member]
SUBTOTAL LONG-TERM DEBT	1,000	1,000
Amortizing Secured Note, due December 20, 2021 [Member]
SUBTOTAL LONG-TERM DEBT	336	643
Amortizing Secured Note, due May 19, 2028 [Member]
SUBTOTAL LONG-TERM DEBT	3,115	3,535
Amortizing Secured Note, due August 25, 2030 [Member]
SUBTOTAL LONG-TERM DEBT	2,707	2,987
Amortizing Secured Note, due September 19, 2031 [Member]
SUBTOTAL LONG-TERM DEBT	2,987	3,267
State Revolving Trust Note, due December 31, 2022 [Member]
SUBTOTAL LONG-TERM DEBT	119	175
State Revolving Trust Note, due May 1, 2025 [Member]
SUBTOTAL LONG-TERM DEBT	1,170	1,405
State Revolving Trust Note, due March 1, 2026 [Member]
SUBTOTAL LONG-TERM DEBT	266	309
State Revolving Trust Note, due January 25, 2027 [Member]
SUBTOTAL LONG-TERM DEBT	307	349
State Revolving Trust Note, due December 1, 2026 [Member]
SUBTOTAL LONG-TERM DEBT	389	446
State Revolving Trust Bond 4.00% to 5.00%, due August 1, 2021 [Member]
SUBTOTAL LONG-TERM DEBT		60
State Revolving Trust Bond 0.00%, due August 1, 2021 [Member]
SUBTOTAL LONG-TERM DEBT	11	50
State Revolving Trust Note, due July 1, 2028 [Member]
SUBTOTAL LONG-TERM DEBT	192	214
State Revolving Trust Note, due January 1, 2028 [Member]
SUBTOTAL LONG-TERM DEBT	62	69
State Revolving Trust Note, due August 1, 2031 [Member]
SUBTOTAL LONG-TERM DEBT	793	851
Amortizing Secured Note, due April 20, 2029 [Member]
SUBTOTAL LONG-TERM DEBT	2,907	3,255
Amortizing Secured Note 7.05%, due January 20, 2030 [Member]
SUBTOTAL LONG-TERM DEBT	2,271	2,521
Amortizing Secured Note 5.69%, due January 20, 2030 [Member]
SUBTOTAL LONG-TERM DEBT	4,658	5,171
4.45%, Amortizing Secured Note, due April 20, 2040 [Member]
SUBTOTAL LONG-TERM DEBT	8,506	8,946
4.47%, Amortizing Secured Note, due April 20, 2040 [Member]
SUBTOTAL LONG-TERM DEBT	3,156	3,320
State Revolving Trust Note, due July 1, 2031 [Member]
SUBTOTAL LONG-TERM DEBT	1,699	1,829
State Revolving Trust Note, due February 1, 2036 [Member]
SUBTOTAL LONG-TERM DEBT	961	1,013
State Revolving Trust Note, due February 1, 2038 [Member]
SUBTOTAL LONG-TERM DEBT	1,543	1,309
State Revolving Trust Note, due November 30, 2030 [Member]
SUBTOTAL LONG-TERM DEBT	883	955
Construction Loans [Member]
SUBTOTAL LONG-TERM DEBT	50,536	40,467
First Mortgage Bonds - Series BB [Member]
SUBTOTAL LONG-TERM DEBT	119	241
First Mortgage Bonds - Series CC [Member]
SUBTOTAL LONG-TERM DEBT	164	331
First Mortgage Bonds - Series EE [Member]
SUBTOTAL LONG-TERM DEBT	1,036	1,456
First Mortgage Bonds - Series FF [Member]
SUBTOTAL LONG-TERM DEBT	1,870	2,440
First Mortgage Bonds - Series GG [Member]
SUBTOTAL LONG-TERM DEBT	541	632
First Mortgage Bonds - Series HH [Member]
SUBTOTAL LONG-TERM DEBT	620	710
First Mortgage Bonds - Series II [Member]
SUBTOTAL LONG-TERM DEBT	338	429
First Mortgage Bonds - Series JJ [Member]
SUBTOTAL LONG-TERM DEBT	500	588
First Mortgage Bonds - Series KK [Member]
SUBTOTAL LONG-TERM DEBT	719	807
First Mortgage Bonds - Series LL [Member]
SUBTOTAL LONG-TERM DEBT	846	928
First Mortgage Bonds - Series MM [Member]
SUBTOTAL LONG-TERM DEBT	937	1,037
First Mortgage Bonds - Series NN [Member]
SUBTOTAL LONG-TERM DEBT	1,105	1,190
First Mortgage Bonds - Series OO [Member]
SUBTOTAL LONG-TERM DEBT	1,656	1,806
First Mortgage Bonds - Series PP [Member]
SUBTOTAL LONG-TERM DEBT	600	660
First Mortgage Bonds - Series QQ [Member]
SUBTOTAL LONG-TERM DEBT	9,915	9,915
First Mortgage Bonds - Series RR [Member]
SUBTOTAL LONG-TERM DEBT	22,500	22,500
First Mortgage Bonds - Series SS [Member]
SUBTOTAL LONG-TERM DEBT	23,000	23,000
First Mortgage Bonds - Series TT [Member]
SUBTOTAL LONG-TERM DEBT	1,806	1,957
First Mortgage Bonds - Series UU [Member]
SUBTOTAL LONG-TERM DEBT	705	755
First Mortgage Bonds - Series VV [Member]
SUBTOTAL LONG-TERM DEBT	1,861	2,004
First Mortgage Bonds - Series WW [Member]
SUBTOTAL LONG-TERM DEBT	715	755
First Mortgage Bonds - Series XX [Member]
SUBTOTAL LONG-TERM DEBT	10,247	10,627
First Mortgage Bonds - Series YY [Member]
SUBTOTAL LONG-TERM DEBT	3,710	3,785
First Mortgage Bonds - Series 2018A [Member]
SUBTOTAL LONG-TERM DEBT	6,246	6,678
First Mortgage Bonds - Series 2018B [Member]
SUBTOTAL LONG-TERM DEBT	2,211	2,320
First Mortgage Bonds - Series 2019A [Member]
SUBTOTAL LONG-TERM DEBT	32,500	32,500
First Mortgage Bonds - Series 2019B [Member]
SUBTOTAL LONG-TERM DEBT	21,200	21,200
First Mortgage Bonds - Series 2020A [Member]
SUBTOTAL LONG-TERM DEBT	$ 40,000

CONSOLIDATED STATEMENTS OF CA_3

CONSOLIDATED STATEMENTS OF CAPITAL STOCK AND LONG-TERM DEBT (Parenthetical) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Common Stock, Shares Authorized	40,000	40,000
Common Stock, Shares Outstanding	17,473	17,434
Preferred Stock, Shares Authorized	120	120
Preferred Stock, Shares Outstanding	20	20
Convertible Preferred Stock $7.00 Series
Common Stock, Shares Outstanding	10	10
Nonredeemable Preferred Stock $7.00 Series
Common Stock, Shares Outstanding	1	1
Nonredeemable Preferred Stock $4.75 Series [Member]
Common Stock, Shares Outstanding	10	10
Amortizing Secured Note, due December 20, 2021 [Member]
Due date of debt	Dec. 20, 2021
Interest rate	8.05%
Amortizing Secured Note, due May 19, 2028 [Member]
Due date of debt	May 19, 2028
Interest rate	6.25%
Amortizing Secured Note, due August 25, 2030 [Member]
Due date of debt	Aug. 25, 2030
Interest rate	6.44%
Amortizing Secured Note, due September 19, 2031 [Member]
Due date of debt	Sep. 19, 2031
Interest rate	6.46%
State Revolving Trust Note, due December 31, 2022 [Member]
Due date of debt	Dec. 31, 2022
Interest rate	4.22%
State Revolving Trust Note, due May 1, 2025 [Member]
Due date of debt	May 1, 2025
Interest rate	3.60%
State Revolving Trust Note, due March 1, 2026 [Member]
Due date of debt	Mar. 1, 2026
Interest rate	3.30%
State Revolving Trust Note, due January 25, 2027 [Member]
Due date of debt	Jan. 25, 2027
Interest rate	3.49%
State Revolving Trust Note, due December 1, 2026 [Member]
Due date of debt	Dec. 1, 2026
Interest rate	4.03%
State Revolving Trust Bond 4.00% to 5.00%, due August 1, 2021 [Member]
Due date of debt	Aug. 1, 2021
State Revolving Trust Bond 0.00%, due August 1, 2021 [Member]
Due date of debt	Aug. 1, 2021
Interest rate	0.00%
State Revolving Trust Note, due July 1, 2028 [Member]
Due date of debt	Jul. 1, 2028
Interest rate	3.64%
State Revolving Trust Note, due January 1, 2028 [Member]
Due date of debt	Jan. 1, 2028
Interest rate	3.64%
State Revolving Trust Note, due August 1, 2031 [Member]
Due date of debt	Aug. 1, 2031
Interest rate	3.45%
Amortizing Secured Note, due April 20, 2029 [Member]
Due date of debt	Apr. 20, 2029
Interest rate	6.59%
Amortizing Secured Note 7.05%, due January 20, 2030 [Member]
Due date of debt	Jan. 20, 2030
Interest rate	7.05%
Amortizing Secured Note 5.69%, due January 20, 2030 [Member]
Due date of debt	Jan. 20, 2030
Interest rate	5.69%
4.45%, Amortizing Secured Note, due April 20, 2040 [Member]
Due date of debt	Apr. 20, 2040
Interest rate	4.45%
4.47%, Amortizing Secured Note, due April 20, 2040 [Member]
Due date of debt	Apr. 20, 2040
Interest rate	4.47%
State Revolving Trust Note, due July 1, 2031 [Member]
Due date of debt	Jul. 1, 2031
Interest rate	3.75%
State Revolving Trust Note, due February 1, 2036 [Member]
Due date of debt	Feb. 1, 2036
Interest rate	2.00%
State Revolving Trust Note, due February 1, 2038 [Member]
Due date of debt	Nov. 1, 2038
Interest rate	2.00%
State Revolving Trust Note, due November 30, 2030 [Member]
Due date of debt	Nov. 30, 2030
Interest rate	3.75%
Construction Loans [Member]
Interest rate	0.00%
First Mortgage Bonds - Series BB [Member]
Due date of debt	Aug. 1, 2021
Interest rate	0.00%
First Mortgage Bonds - Series CC [Member]
Due date of debt	Aug. 1, 2021
First Mortgage Bonds - Series CC [Member] \| Minimum [Member]
Interest rate	4.00%
First Mortgage Bonds - Series CC [Member] \| Maximum [Member]
Interest rate	5.00%
First Mortgage Bonds - Series EE [Member]
Due date of debt	Aug. 1, 2023
Interest rate	0.00%
First Mortgage Bonds - Series FF [Member]
Due date of debt	Aug. 1, 2024
First Mortgage Bonds - Series FF [Member] \| Minimum [Member]
Interest rate	3.00%
First Mortgage Bonds - Series FF [Member] \| Maximum [Member]
Interest rate	5.50%
First Mortgage Bonds - Series GG [Member]
Due date of debt	Aug. 1, 2026
Interest rate	0.00%
First Mortgage Bonds - Series HH [Member]
Due date of debt	Aug. 1, 2026
First Mortgage Bonds - Series HH [Member] \| Minimum [Member]
Interest rate	4.00%
First Mortgage Bonds - Series HH [Member] \| Maximum [Member]
Interest rate	5.00%
First Mortgage Bonds - Series II [Member]
Due date of debt	Aug. 1, 2024
Interest rate	0.00%
First Mortgage Bonds - Series JJ [Member]
Due date of debt	Aug. 1, 2027
First Mortgage Bonds - Series JJ [Member] \| Minimum [Member]
Interest rate	3.40%
First Mortgage Bonds - Series JJ [Member] \| Maximum [Member]
Interest rate	5.00%
First Mortgage Bonds - Series KK [Member]
Due date of debt	Aug. 1, 2028
Interest rate	0.00%
First Mortgage Bonds - Series LL [Member]
Due date of debt	Aug. 1, 2028
First Mortgage Bonds - Series LL [Member] \| Minimum [Member]
Interest rate	5.00%
First Mortgage Bonds - Series LL [Member] \| Maximum [Member]
Interest rate	5.50%
First Mortgage Bonds - Series MM [Member]
Due date of debt	Aug. 1, 2030
Interest rate	0.00%
First Mortgage Bonds - Series NN [Member]
Due date of debt	Aug. 1, 2030
First Mortgage Bonds - Series NN [Member] \| Minimum [Member]
Interest rate	3.00%
First Mortgage Bonds - Series NN [Member] \| Maximum [Member]
Interest rate	4.375%
First Mortgage Bonds - Series OO [Member]
Due date of debt	Aug. 1, 2031
Interest rate	0.00%
First Mortgage Bonds - Series PP [Member]
Due date of debt	Aug. 1, 2031
First Mortgage Bonds - Series PP [Member] \| Minimum [Member]
Interest rate	2.00%
First Mortgage Bonds - Series PP [Member] \| Maximum [Member]
Interest rate	5.00%
First Mortgage Bonds - Series QQ [Member]
Due date of debt	Oct. 1, 2023
Interest rate	5.00%
First Mortgage Bonds - Series RR [Member]
Due date of debt	Oct. 1, 2038
Interest rate	3.80%
First Mortgage Bonds - Series SS [Member]
Due date of debt	Oct. 1, 2047
Interest rate	4.25%
First Mortgage Bonds - Series TT [Member]
Due date of debt	Aug. 1, 2032
Interest rate	0.00%
First Mortgage Bonds - Series UU [Member]
Due date of debt	Aug. 1, 2032
First Mortgage Bonds - Series UU [Member] \| Minimum [Member]
Interest rate	3.00%
First Mortgage Bonds - Series UU [Member] \| Maximum [Member]
Interest rate	3.25%
First Mortgage Bonds - Series VV [Member]
Due date of debt	Aug. 1, 2033
Interest rate	0.00%
First Mortgage Bonds - Series WW [Member]
Due date of debt	Aug. 1, 2033
First Mortgage Bonds - Series WW [Member] \| Minimum [Member]
Interest rate	3.00%
First Mortgage Bonds - Series WW [Member] \| Maximum [Member]
Interest rate	5.00%
First Mortgage Bonds - Series XX [Member]
Due date of debt	Aug. 1, 2047
Interest rate	0.00%
First Mortgage Bonds - Series YY [Member]
Due date of debt	Aug. 1, 2047
First Mortgage Bonds - Series YY [Member] \| Minimum [Member]
Interest rate	3.00%
First Mortgage Bonds - Series YY [Member] \| Maximum [Member]
Interest rate	5.00%
First Mortgage Bonds - Series 2018A [Member]
Due date of debt	Aug. 1, 2047
Interest rate	0.00%
First Mortgage Bonds - Series 2018B [Member]
Due date of debt	Aug. 1, 2047
First Mortgage Bonds - Series 2018B [Member] \| Minimum [Member]
Interest rate	3.00%
First Mortgage Bonds - Series 2018B [Member] \| Maximum [Member]
Interest rate	5.00%
First Mortgage Bonds - Series 2019A [Member]
Due date of debt	Aug. 1, 2059
Interest rate	4.00%
First Mortgage Bonds - Series 2019B [Member]
Due date of debt	Aug. 1, 2059
Interest rate	5.00%
First Mortgage Bonds - Series 2020A [Member]
Due date of debt	Nov. 18, 2050
Interest rate	2.90%

CONSOLIDATED STATEMENTS OF COMM

CONSOLIDATED STATEMENTS OF COMMON STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock [Member]	Retained Earnings [Member]	Total
Balance at Dec. 31, 2017	$ 155,120	$ 74,055	$ 229,175
Balance, shares at Dec. 31, 2017	16,352
Net Income		32,452	32,452
Dividend Reinvestment & Common Stock Purchase Plan	$ 1,150		1,150
Dividend Reinvestment & Common Stock Purchase Plan, shares	27,000
Restricted Stock Award, Net - Employees	$ 975		975
Restricted Stock Award, Net - Employees, shares	22,000
Stock Award - Board Of Directors	$ 147		147
Stock Award - Board Of Directors, shares	4,000
Shares Forefeited	$ (38)		(38)
Shares Forfeited, shares	(2,000)
Cash Dividends on Common Stock		(14,930)	(14,930)
Cash Dividends on Preferred Stock		(144)	(144)
Balance at Dec. 31, 2018	$ 157,354	91,433	248,787
Balance, shares at Dec. 31, 2018	16,403
Net Income		33,888	33,888
Dividend Reinvestment & Common Stock Purchase Plan	$ 12,738		12,738
Dividend Reinvestment & Common Stock Purchase Plan, shares	226,000
Restricted Stock Award, Net - Employees	$ 907		907
Restricted Stock Award, Net - Employees, shares	18,000
Stock Award - Board Of Directors	$ 196		196
Stock Award - Board Of Directors, shares	4,000
Shares Forefeited	$ (466)		(466)
Shares Forfeited, shares	(18,000)
Conversion of Convertible Preferred Stock	$ 350		350
Conversion of Convertible Preferred Stock, shares	41,000
Issuance of Common Stock	$ 44,046		44,046
Issuance of Common Stock, shares	760,000
Cash Dividends on Common Stock		(16,165)	(16,165)
Cash Dividends on Preferred Stock		(132)	(132)
Common Stock Expenses		(357)	(357)
Balance at Dec. 31, 2019	$ 215,125	108,667	323,792
Balance, shares at Dec. 31, 2019	17,434,000
Net Income		38,425	38,425
Dividend Reinvestment & Common Stock Purchase Plan	$ 1,230		1,230
Dividend Reinvestment & Common Stock Purchase Plan, shares	19,000
Restricted Stock Award, Net - Employees	$ 851		851
Restricted Stock Award, Net - Employees, shares	16,000
Stock Award - Board Of Directors	$ 245		245
Stock Award - Board Of Directors, shares	4,000
Cash Dividends on Common Stock		(18,178)	(18,178)
Cash Dividends on Preferred Stock		(120)	(120)
Common Stock Expenses		(37)	(37)
Balance at Dec. 31, 2020	$ 217,451	$ 128,757	$ 346,208
Balance, shares at Dec. 31, 2020	17,473,000

CONSOLIDATED STATEMENTS OF CO_2

CONSOLIDATED STATEMENTS OF COMMON STOCKHOLDERS' EQUITY (Parenthetical)	12 Months Ended
	Dec. 31, 2019$ / shares
Statement of Stockholders' Equity [Abstract]
Cash dividends paid, per share	$ 0.976
Conversion price	$ 8

Organization, Summary of Signif

Organization, Summary of Significant Accounting Policies and Recent Developments	12 Months Ended
	Dec. 31, 2020
Organization Summary Of Significant Accounting Policies And Recent Developments [Abstract]
Organization, Summary of Significant Accounting Policies and Recent Developments	Note 1 - Organization, Summary of Significant Accounting Policies and Recent Developments (a) Organization Middlesex Water Company has operated as a water utility in New Jersey since 1897 and in Delaware, through our wholly-owned subsidiary, Tidewater, since 1992. We are in the business of collecting, treating, distributing and selling water for domestic, commercial, municipal, industrial and fire protection purposes. We also operate New Jersey municipal water, wastewater and storm water systems under contract and provide unregulated water and wastewater services in New Jersey and Delaware through our subsidiaries. Our rates charged to customers for water and wastewater services, the quality of services we provide and certain other matters are regulated in New Jersey, Delaware and Pennsylvania by the New Jersey Board of Public Utilities (NJBPU), Delaware Public Service Commission (DEPSC) and Pennsylvania Public Utilities Commission (PAPUC), respectively. Our USA, USA-PA and White Marsh subsidiaries are not regulated utilities. (b) Principles of Consolidation - (c) System of Accounts - (d) Regulatory Accounting Regulated Operations In accordance with ASC 980, Regulated Operations Rate and Regulatory Matters (e) Retirement Benefit Plans 45 Index (Other Benefits Plan) for substantially all of its retired employees. Employees hired after March 31, 2007 are not eligible to participate in this plan. Coverage includes healthcare and life insurance. The Company’s costs for providing retirement benefits are dependent upon numerous factors, including actual plan experience and assumptions of future experience. Retirement benefit plan obligations and expense are determined based on investment performance, discount rates and various other demographic factors related to the population participating in the Company’s retirement benefit plans, all of which can change significantly in future years. For more information on the Company’s Retirement Benefit Plans, see Note 7 – Employee Benefit Plans (f) Utility Plant - (g) Depreciation - Source of Supply 1.15% - 3.44% Transmission and Distribution (T&D): Pumping 2.00% - 5.39% T&D – Mains 1.10% - 3.13% Water Treatment 1.65% - 7.09% T&D – Services 2.12% - 3.16% General Plant 2.08% - 17.84% T&D – Other 1.61% - 4.63% Wastewater Collection 1.42% - 1.81% Non-regulated fixed assets consist primarily of office buildings, furniture and fixtures, and transportation equipment. These assets are recorded at original cost and depreciation is calculated based on the estimated useful lives, ranging from 3 to 42 years. (h) Preliminary Survey and Investigation (PS&I) Costs - (i) Customers’ Advances for Construction (CAC) - Contributions in Aid of Construction (CIAC) CAC and CIAC are not depreciated in accordance with regulatory requirements. In addition, these amounts reduce the investment base for purposes of setting rates. 46 Index (j) Allowance for Funds Used During Construction (AFUDC) 2020 2019 2018 Middlesex 6.50% 6.50% 6.50% Tidewater 7.92% 7.92% 7.92% (k) Accounts Receivable Note 1 (s), COVID-19 (l) Revenues The Company’s regulated revenue from contracts with customers is derived from tariff-based sales that result from the obligation to provide water and wastewater services to residential, industrial, commercial, fire-protection and wholesale customers. The Company’s residential customers are billed quarterly while most of the Company’s industrial, commercial, fire-protection and wholesale customers are billed monthly. Payments by customers are due between 15 to 30 days after the invoice date. The Company recognizes revenue as the water and wastewater services are delivered to customers as well as records unbilled revenues estimated from the last meter reading date to the end of the accounting period utilizing factors such as historical customer data, regional weather indicators and general economic conditions in its service territories. Unearned Revenues and Advance Service Fees include fixed service charge billings in advance to Tidewater customers that are recognized as service is provided to the customer. Non-regulated service contract revenues consist of base service fees as well as fees for additional billable services provided to customers. Fees are billed monthly and are due within 30 days after the invoice date. The Company considers the amounts billed to represent the value of these services provided to customers. These contracts expire at various times through June 2030 and contain remaining performance obligations for which the Company expects to recognize revenue in the future. These contracts also contain customary termination provisions. Almost all of the amounts included in operating revenues and accounts receivable are from contracts with customers. The Company records its allowance for doubtful accounts based on historical write-offs combined with an evaluation of current economic conditions within its service territories. The Company’s contracts do not contain any significant financing components. 47 Index The Company’s operating revenues are comprised of the following: (In Thousands) Years Ended December 31, 2020 2019 2018 Regulated Tariff Sales Residential $ 76,798 $ 71,487 $ 69,785 Commercial 15,448 15,198 14,844 Industrial 9,512 9,390 10,183 Fire Protection 12,374 12,291 12,099 Wholesale 15,187 14,319 14,655 Non-Regulated Contract Operations 12,130 11,773 16,374 Total Revenue from Contracts with Customers $ 141,449 $ 134,458 $ 137,940 Other Regulated Revenues 532 393 335 Other Non-Regulated Revenues 415 404 404 Inter-segment Elimination (804 ) (657 ) (602 ) Total Revenue $ 141,592 $ 134,598 $ 138,077 (m) Unamortized Debt Expense and Premiums on Long-Term Debt (n) Income Taxes Income Taxes (o) Cash and Cash Equivalents (p) Restricted Cash (q) Use of Estimates (r) Recent Accounting Pronouncements Leases - Leases Note 4 – Commitments and Contingent Liabilities 48 Index Credit Losses on Financial Instruments - Expected credit losses on accounts receivable and unbilled revenues are based on historical write-offs combined with an evaluation of current conditions and reasonable and supportable forecasts. Customer accounts are written off when collection efforts have been exhausted. There are no other new adopted or proposed accounting guidance that the Company is aware of that could have a material impact on the Company’s consolidated financial statements. (s) COVID-19 The NJBPU and the DEPSC have allowed for potential future recovery of COVID-19 related incremental costs through customer rates by the regulated utilities under their respective jurisdictions. Neither jurisdiction has yet to establish a timetable or definitive formal procedures for seeking cost recovery. We will continue to monitor the COVID-19 situation and evaluate its impact on the Company’s business, results of operations, financial condition and liquidity.

Rate and Regulatory Matters

Rate and Regulatory Matters	12 Months Ended
Rate and Regulatory Matters	Dec. 31, 2020
Regulated Operations [Abstract]
Rate and Regulatory Matters	Note 2 - Rate and Regulatory Matters Rate Matters Middlesex In March 2020, the NJBPU approved Middlesex’s petition to reset its PWAC tariff rate to recover additional costs of $0.6 million for the purchase of treated water from a non-affiliated water utility regulated by the NJBPU. The new PWAC rate became effective on April 4, 2020. In March 2018, Middlesex’s petition to the NJBPU seeking permission to increase its base water rates was concluded, based on a negotiated settlement, resulting in an increase in annual operating revenues of $5.5 million. The approved base water rates were designed to recover increased operating costs as well as a return on invested capital in rate base of $245.5 million, based on an authorized return on common equity of 9.6%. As part of the settlement, Middlesex received approval for regulatory accounting treatment of income tax benefits associated with required adoption of tangible property regulations issued by the Internal Revenue Service. The settlement agreement allowed for a four-year amortization period for $28.7 million of deferred income tax benefits as well as prospective recognition of the income tax benefits for the immediate deduction of repair costs on tangible property. The rate increase became effective April 1, 2018. 49 Index Tidewater - In November 2019, Tidewater completed a $1.8 million DEPSC-approved purchase of the water utility assets of J.H. Wilkerson and Son, Inc. and transfer of the Certificate of Public Convenience and Necessity in order for Tidewater to serve the approximate 1,000 customers currently connected to eight community water systems located mostly in eastern Sussex County, Delaware. The DEPSC also authorized Tidewater to maintain the existing customer rates. Effective March 1, 2019, Tidewater received approval from the DEPSC to reduce its rates to reflect the lower corporate income tax rate enacted by the Tax Cuts and Jobs Act of 2017 ( 2017 Tax Act), resulting in a 3.35% rate decrease for certain customer classes. Pinelands - Southern Shores - Twin Lakes Utilities, Inc. (Twin Lakes) - 50 Index Regulatory Matters We have recorded certain costs as regulatory assets because we expect full recovery of, or are currently recovering, these costs in the rates we charge customers. These deferred costs have been excluded from rate base and, therefore, we are not earning a return on the unamortized balances. These items are detailed as follows: (Thousands of Dollars) December 31, Remaining Regulatory Assets 2020 2019 Recovery Periods Retirement Benefits $ 45,419 $ 44,281 Various Income Taxes 66,759 60,151 Various Rate Cases, Tank Painting, and Other 5,966 6,047 2-10 years Total $ 118,144 $ 110,479 Retirement benefits include pension and other retirement benefits that have been recorded on the Consolidated Balance Sheet in accordance with the guidance provided in ASC 715 , Compensation – Retirement Benefits. The recovery period for income taxes is dependent upon when the temporary differences between the tax and book treatment of various items reverse. The 2017 Tax Act reduced the statutory corporate federal income tax rate from 35% to 21% . The tariff rates charged to customers effective prior to 2018 in the Company’s regulated companies include recovery of income taxes at the statutory rate in effect at the time those rates were approved by the respective state public utility commissions. As of December 31, 2020 and December 31, 2019, the Company has recorded regulatory liabilities of $31.0 million and $31.5 million, respectively for excess income taxes collected through rates due to the lower income tax rate under the 2017 Tax Act. These regulatory liabilities are overwhelmingly related to utility plant depreciation deduction timing differences, which are subject to Internal Revenue Service (IRS) normalization rules. The IRS rules limit how quickly the excess taxes attributable to accelerated taxes can be returned to customers. The current base rates for Middlesex, Pinelands and Twin Lakes’ customers became effective after 2017 and reflect the impact of the 2017 Tax Act on their revenue requirements. In February 2019, Tidewater received approval from the DEPSC to reduce its base rates to reflect the lower statutory corporate income tax rate enacted by the 2017 Tax Act (see Rate Matters-Tidewater As part of Middlesex’s March 2018 base water rate settlement with the NJBPU, Middlesex received approval for regulatory accounting treatment of income tax benefits associated with the adoption of tangible property regulations issued by the IRS (see Rate Matters-Middlesex The Company uses composite depreciation rates for its regulated utility assets, which is currently an acceptable method under generally accepted accounting principles and is widely used in the utility industry. Historically, under the composite depreciation method, the anticipated costs of removing assets upon retirement are provided for over the life of those assets as a component of depreciation expense. The Company recovers certain asset retirement costs through rates charged to customers as an approved component of depreciation expense. As of December 31, 2020 and 2019, the Company has approximately $14.9 million and $13.4 million, respectively, of expected costs of removal recovered currently in rates in excess of actual costs incurred as regulatory liabilities.

Income Taxes

Income Taxes	12 Months Ended
Income Taxes	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Note 3 - Income Taxes Income tax (benefit) expense differs from the amount computed by applying the statutory rate on book income subject to tax for the following reasons: (Thousands of Dollars) Years Ended December 31, 2020 2019 2018 Income Tax at Statutory Rate $ 7,204 $ 6,457 $ 7,009 Tax Effect of: Utility Plant Related (1,356 ) (802 ) 422 Tangible Property Repairs (11,298 ) (10,156 ) (7,763 ) State Income Taxes – Net 1,364 1,173 1,207 Other (33 ) 188 49 Total Income Tax (Benefit) Expense $ (4,119 ) $ (3,140 ) $ 924 Income tax (benefit) expense is comprised of the following: (Thousands of Dollars) Years Ended December 31, 2020 2019 2018 Current: Federal $ (4,281 ) $ (3,822 ) $ (188 ) State 2,598 2,246 2,073 Deferred: Federal (1,490 ) (726 ) (338 ) State (871 ) (761 ) (545 ) Investment Tax Credits (75 ) (77 ) (78 ) Total Income Tax (Benefit) Expense $ (4,119 ) $ (3,140 ) $ 924 As part of Middlesex’s March 2018 base water rate settlement with the NJBPU, Middlesex received approval for regulatory accounting treatment of income tax benefits associated with the adoption of tangible property regulations issued by the IRS as well as prospective recognition of the income tax benefits for the immediate deduction of repair costs on tangible property (see Note 2 – Rate and Regulatory Matters 52 Index Deferred income taxes reflect the net tax effect of temporary differences between the carrying amounts of assets and liabilities for financial purposes and the amounts used for income tax purposes. The components of the net deferred tax liability are as follows: (Thousands of Dollars) December 31, 2020 2019 Utility Plant Related $ 56,868 $ 50,608 Customer Advances (3,626 ) (3,661 ) Employee Benefits 7,339 6,543 Investment Tax Credits 445 519 Other 271 399 Total Accumulated Deferred Income Taxes $ 61,297 $ 54,408 The Company’s federal income tax returns for the tax years 2014 through 2017 were selected for examination by the IRS, which included the tax year in which the Company had adopted the final IRS tangible property regulations and changed its accounting method for the tax treatment of expenditures that qualified as deductible repairs. As a result of the audit examination, the Company agreed to certain modifications of its accounting method for expenditures that qualify as deductible repairs. In 2019, the Company paid $2.7 million in income taxes and $0.1 million in interest in connection with the conclusion of the 2014 through 2017 federal income tax return audits. As of December 31, 2020, the Company has reduced its income tax reserve provision and interest expense liability to $0.5 million and $0.1 million, respectively. The statutory review periods for federal income tax returns for the years prior to 2017 have been closed. Other than the effects of the provision against refundable taxes discussed above, there are no unrecognized tax benefits resulting from prior period tax positions.

Commitments and Contingent Liab

Commitments and Contingent Liabilities	12 Months Ended
Commitments and Contingent Liabilities	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingent Liabilities	Note 4 - Commitments and Contingent Liabilities Water Supply Middlesex also has an agreement with a non-affiliated NJBPU-regulated water utility for the purchase of treated water. This agreement, which expires February 27, 2026, provides for the minimum purchase of 3.0 mgd of treated water with provisions for additional purchases if needed. Tidewater contracts with the City of Dover, Delaware to purchase treated water of 15.0 million gallons annually. Purchased water costs are shown below: (Millions of Dollars) Years Ended December 31, 2020 2019 2018 Untreated $ 3.4 $ 3.4 $ 3.6 Treated 3.6 3.2 3.2 Total Costs $ 7.0 $ 6.6 $ 6.8 Guarantees - 53 Index In November 2019, Middlesex was notified that the County terminated its Agreement with the Contractor. The Contractor had initiated legal action against the County that in part contests the County’s exercise of this termination. The County filed a counter-claim against the Contractor’s parent company and has brought Middlesex into the suit as a third-party defendant. We continue to monitor this litigation; however, given the cancellation of the underlying operating contract by the County and the continuation of the litigation matter, we do not anticipate having to perform under the guaranty nor do we anticipate the ultimate outcome will have a material impact on the Company’s results of operations or financial condition. Based on the foregoing, the liability and asset for the guaranty, included in Other Non-Current Liabilities and Other Non-Current Assets on the balance sheet, was reduced from $1.4 million as of December 31, 2019 to $0 at December 31, 2020. Leases - The Company has an operating lease for office space for administrative purposes, expiring in 2030. The Company has not entered into any finance leases. The exercise of a lease renewal option for the Company’s administrative offices is solely at the discretion of the Company. The right-of-use (ROU) asset recorded represents the Company’s right to use an underlying asset for the lease term and lease liability represents the Company’s obligation to make lease payments arising from the lease. Lease ROU assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. The Company’s operating lease does not provide an implicit discount rate and as such the Company used an estimated incremental borrowing rate (4.03%) based on the information available at commencement date in determining the present value of lease payments. Given the impacts of accounting for regulated operations, and the resulting recognition of expense at the amounts recovered in customer rates, expenditures for operating leases are consistent with lease expense and was $0.8 million, $0.7 million and $0.5 million for the years ended December 31, 2020, 2019 and 2018, respectively. Information related to operating lease ROU assets is as follows: (In Millions December 31, 2020 2019 ROU Asset at Least Inception $ 7.3 $ 7.3 Accumulated Amortization (2.1 ) (1.4 ) Current ROU Asset $ 5.2 $ 5.9 54 Index The Company’s future minimum operating lease commitments as of December 31, 2020 are as follows: (In Millions) December 31, 2020 2021 0.8 2022 0.8 2023 0.8 2024 0.8 2025 0.8 Thereafter 3.6 Total Lease Payments $ 7.6 Imputed Interest (1.9 ) Present Value of Lease Payments 5.7 Less Current Portion* (0.7 ) Non-Current Lease Liability $ 5.0 * Included in Other Current Liabilities Construction Note 1(s) COVID-19 Contingencies Change in Control Agreements

Short-term Borrowings

Short-term Borrowings	12 Months Ended
Short-term Borrowings	Dec. 31, 2020
Short-term Debt [Abstract]
Short-term Borrowings	Note 5 - Short-term Borrowings Information regarding the Company’s short-term borrowings for the years ended December 31, 2020 and 2019 is summarized below: (Millions of Dollars) 2020 2019 Average Amount Outstanding $ 28.3 $ 52.4 Weighted Average Interest Rate 1.55 % 3.33 % Notes Payable at Year-End $ 2.0 $ 20.0 Weighted Average Interest Rate at Year-End 1.04 % 2.86 % 55 Index The Company maintained lines of credit aggregating $140.0 million at December 31, 2020 and 2019. (Millions) As of December 31, 2020 Line of Credit Outstanding Available Maximum Credit Type Renewal Date Bank of America $ - $ 60.0 $ 60.0 Uncommitted January 28, 2021 PNC Bank 2.0 66.0 68.0 Committed January 31, 2022 CoBank - 12.0 12.0 Committed November 30, 2023 $ 2.0 $ 138.0 $ 140.0 The Company's Bank of America line of credit was renewed on January 28, 2021 and reduced to $30.0 million, reducing the Company's total available lines of credit to $110.0 million. The Bank of America line of credit is renewed on an annual basis. The maturity dates for the Notes Payable as of December 31, 2020 are in January 2021 and are extendable at the discretion of the Company. The interest rates for borrowings under the lines of credit are set using the London InterBank Offered Rate (LIBOR) and adding a credit spread, which varies by financial institution. There is no requirement for a compensating balance under any of the established lines of credit.

Capitalization

Capitalization	12 Months Ended
Capitalization	Dec. 31, 2020
CAPITALIZATION:
Capitalization	Note 6 - Capitalization All the transactions discussed below related to the issuance of securities were approved by either the NJBPU or DEPSC, except where otherwise noted. Common Stock In November 2019, the Company sold and issued 0.8 million shares of common stock in a public offering priced at $60.50 per share. The net proceeds of $43.7 million were used for general corporate purposes including repayment of a portion of the Company’s short-term debt. The Company issues shares of its common stock in connection with its Middlesex Water Company Investment Plan (the Investment Plan), a direct share purchase and dividend reinvestment plan for the Company’s common stock. The Company raised approximately $1.2 million under the Investment Plan during 2020. Since the inception of the Investment Plan and its predecessor plan, the Company has periodically replenished the level of authorized shares in the plans. Currently, there remains 0.4 million shares registered with the SEC for the Investment Plan and available for potential issuance to participants. In 2019, the Company raised approximately $12.7 million primarily through a limited duration six-month share purchase discount feature of the Investment Plan. The 0.2 million share purchase limit was reached and the discount offer ceased prior to the original ending date. The Company issues common shares under a restricted stock plan for certain management employees, which is described in Note 7 – Employee Benefit Plans The Company maintains a stock plan for its outside directors (the Outside Director Stock Compensation Plan) as a component of Director compensation. For the years ended December 31, 2020, 2019 and 2018, 4,074, 3,521 and 4,004 shares, respectively, of Middlesex common stock were granted and issued to the Company’s outside directors under the Outside Director Stock Compensation Plan and 52,569 shares remain available for future awards. The maximum number of shares authorized for grant under the Outside Director Stock Compensation Plan is 100,000. In the event dividends on the preferred stock are in arrears, no dividends may be declared or paid on the common stock of the Company. 56 Index Preferred Stock At December 31, 2020 and 2019, there were 120,000 shares of preferred stock authorized and less than 31,000 shares of preferred stock outstanding. There were no preferred stock dividends in arrears. The Company may not pay any dividends on its common stock unless full cumulative dividends to the preceding dividend date for all outstanding shares of preferred stock have been paid or set aside for payment. If four or more quarterly dividends are in arrears, the preferred shareholders, as a class, are entitled to elect two members to the Board of Directors in addition to Directors elected by holders of the common stock. In addition, if Middlesex were to liquidate, holders of preferred stock would be paid back the stated value of their preferred shares before any distributions could be made to common stockholders. The conversion feature of the no par $7.00 Series Cumulative and Convertible Preferred Stock allows the security holders to exchange one convertible preferred share for twelve shares of the Company's common stock. In addition, the Company may redeem up to 10% of the outstanding convertible stock in any calendar year at a price equal to the fair value of twelve shares of the Company's common stock for each share of convertible stock redeemed. In 2019, all remaining outstanding no par $8.00 Series Cumulative and Convertible Preferred Stock were converted into the Company’s common stock. Long-term Debt Subject to regulatory approval, the Company periodically issues long-term debt to fund its investments in utility plant. To the extent possible, the Company finances qualifying capital projects under State Revolving Fund (SRF) loan programs in New Jersey and Delaware. These government programs provide financing at interest rates that are typically below rates available in the broader financial markets. A portion of the borrowings under the New Jersey SRF is interest-free. Under the New Jersey SRF program, borrowers first enter into a construction loan agreement with the New Jersey Infrastructure Bank (NJIB) at a below market interest rate. The interest rate on the Company’s current construction loan borrowings is zero percent (0%). When construction on the qualifying project is substantially complete, NJIB will coordinate the conversion of the construction loan into a long-term securitized loan with a portion of the principal balance having a stated interest rate of zero percent (0%) and a portion of the principal balance at a market interest rate at the time of closing using the credit rating of the State of New Jersey. The term of the long-term loans currently offered through the NJIB is up to thirty years. The NJIB generally schedules its long-term debt financings in May and November. Middlesex currently has two projects that are in the construction loan phase of the New Jersey SRF program as follows: 1) In April 2018, the NJBPU approved Middlesex’s request to participate in the NJIB loan program to fund the construction of a 4.5 mile large-diameter transmission pipeline from the Carl J. Olsen water treatment plant in Edison, New Jersey and interconnect with our distribution system. Middlesex closed on a $43.5 million NJIB interest-free construction loan in August 2018. Through December 31, 2020, Middlesex has drawn a total of $41.9 million and expects to draw any remaining funding requests on this construction loan in the first quarter of 2021. 2) In March 2018, the NJBPU approved Middlesex’s request to participate in the NJIB loan program to fund the 2018 RENEW Program, which is an ongoing initiative to eliminate unlined water distribution mains in the Middlesex system. Middlesex closed on an $8.7 million NJIB construction loan in September 2018 and completed withdrawal of the proceeds in October 2019. The Company expects that the large-diameter transmission pipeline and the 2018 RENEW construction loans will be included in the NJIB May 2021 long-term debt financing program. 57 Index In September 2018, the NJIB announced changes to the SRF program for project funding priority ranking, the proportions of interest free loans and market interest rate loans and overall loan limits on interest free loan balances to investor-owned water utilities. These changes affect SRF projects for which the construction loan closes after September 2018. Under the new guidelines, the principal balance having a stated interest rate of zero percent (0%) is 25% of the loan balance with the remaining portion of 75% having a market based interest rate. This is limited to the first $10.0 million of the loan. Loan amounts above $10.0 million do not participate in the 0% rate program, but do participate at the market based interest rate. As a result of all these changes, the Company’s future capital funding plan currently does not include participating in the NJIB SRF program. In May 2020, Middlesex received approval from the NJBPU to borrow up to $100 million, in one or more private placement transactions through December 31, 2023 to help fund Middlesex’s multi-year capital construction program. In November 2020, Middlesex closed on a $40.0 million private placement loan with a payment maturity date of November 2050 In order to help ensure adherence to its comprehensive financing plan, Middlesex received approval from the NJBPU in February 2019 to issue and sell up to $140 million of FMBs through the NJEDA in one or more transactions through December 31, 2022. Because the interest paid to the bondholders is exempt from federal and New Jersey income taxes, the interest rate on debt issued through the NJEDA is generally lower than otherwise achievable in the traditional taxable corporate bond market. However, the interest received by the bondholder is subject to the Alternative Minimum Tax. In August 2019, Middlesex priced and closed on a NJEDA debt financing transaction of $53.7 million by issuing FMBs designated as Series 2019A ($32.5 million at coupon interest rate of 4.0%) and Series 2019B ($21.2 million at coupon interest rate of 5.0%). The proceeds, including an issuance premium of $7.1 million, are being used to finance several projects under the Water For Tomorrow capital program initiated by the Company to upgrade and replace aging water utility infrastructure. The total proceeds of $60.8 million, initially recorded as Restricted Cash on the balance sheet, are held in escrow by a bond trustee and are drawn down by requisition for the qualifying projects. Through December 31, 2020, Middlesex has drawn a total of $55.1 million and currently expects to draw the remaining $5.7 million of proceeds, currently included in Restricted Cash, through the second quarter of 2021. In March 2018, the DEPSC approved Tidewater’s request to borrow up to $0.9 million under the Delaware SRF program to fund the replacement of an entire water distribution system of a small Delaware community. Tidewater closed on the SRF loan in May 2018. In April 2019, Tidewater received approval from the DEPSC to increase the borrowing to $1.7 million based on revised project cost estimates. Tidewater closed on the additional SRF loan in October 2019 and completed withdrawal of the proceeds in April 2020. FMB Series RR, SS, 2019A, 2019B and 2020A are term bonds with single maturity dates subsequent to 2025. The aggregate annual principal repayment obligations for all long-term debt over the next five years are shown below: Year (Millions of Dollars) Annual Maturities 2021 $ 7.3 2022 $ 6.7 2023 $ 16.1 2024 $ 6.0 2025 $ 5.6 The weighted average interest rate on all long-term debt at December 31, 2020 and 2019 was 3.02% and 3.17%, respectively. Except for the FMB Series 2020A ($40.0 million) and Amortizing Secured Notes ($30.6 million), all of the Company’s outstanding long-term debt has been issued through the NJEDA ($109.1 million), the NJIB SRF program ($89.1 million) and the Delaware SRF program ($8.4 million). 58 Index Substantially all of the utility plant of the Company is subject to the lien of its mortgage, which includes debt service and capital ratio covenants. The Company is in compliance with all of its mortgage covenants and restrictions. Earnings Per Share The following table presents the calculation of basic and diluted earnings per share (EPS) for the years ended December 31, 2020, 2019 and 2018. Basic EPS is computed on the basis of the weighted average number of shares outstanding. Diluted EPS assumes the conversion of both the Convertible Preferred Stock $7.00 Series and $8.00 Series (fully converted into common stock in September 2019). (In Thousands, Except Per Share Amounts) 2020 2019 2018 Basic: Income Shares Income Shares Income Shares Net Income $ 38,425 17,459 $ 33,888 16,685 $ 32,452 16,384 Preferred Dividend (120 ) (132 ) (144 ) Earnings Applicable to Common Stock $ 38,305 17,459 $ 33,756 16,685 $ 32,308 16,384 Basic EPS $ 2.19 $ 2.02 $ 1.97 Diluted: Earnings Applicable to Common Stock $ 38,305 17,459 $ 33,756 16,685 $ 32,308 16,384 $7.00 Series Dividend 67 115 67 115 67 115 $8.00 Series Dividend - - 12 29 24 41 Adjusted Earnings Applicable to Common Stock $ 38,372 17,574 $ 33,835 16,829 $ 32,399 16,540 Diluted EPS $ 2.18 $ 2.01 $ 1.96 Fair Value of Financial Instruments The following methods and assumptions were used by the Company in estimating its fair value disclosure for financial instruments for which it is practicable to estimate that value. The carrying amounts reflected in the consolidated balance sheets for cash and cash equivalents, accounts receivable, accounts payable and notes payable approximate their respective fair values due to the short-term maturities of these instruments. The fair value of First Mortgage and State Revolving Fund Bonds (collectively, the Bonds) issued by Middlesex is based on quoted market prices for similar issues. Under the fair value hierarchy, the fair value of cash and cash equivalents is classified as a Level 1 measurement and the fair value of notes payable and the Bonds in the table below are classified as Level 2 measurements. The carrying amount and fair value of the Bonds were as follows: (Thousands of Dollars) At December 31, 2020 2019 Carrying Fair Carrying Fair Amount Value Amount Value Bonds $ 147,667 $ 159,195 $ 151,361 $ 160,772 For other long-term debt issuances for which there is no quoted market price and there is not an active trading market, it was not practicable to estimate their fair value. For details, including carrying value, interest rate and due date on these series of long-term debt, please refer to those series of long-term debt described as “Amortizing Secured Note”, “State Revolving Trust Note”, “Construction Loans” and “Series 2020A” on the Consolidated Statements of Capital Stock and Long-Term Debt. The carrying amount of these instruments was $129.6 million and $83.0 million at December 31, 2020 and 2019, respectively. Customer advances for construction have carrying amounts of $23.4 million and $23.9 million at December 31, 2020 and 2019, respectively. Their relative fair values cannot be accurately estimated since future refund payments depend on several variables, including new customer connections, customer consumption levels and future rate increases.

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
Employee Benefit Plans	Dec. 31, 2020
Retirement Benefits [Abstract]
Employee Benefit Plans	Note 7 - Employee Benefit Plans Pension Benefits The Company’s Pension Plan covers all active employees hired prior to April 1, 2007. Employees hired after March 31, 2007 are not eligible to participate in this plan, but can participate in a defined contribution profit sharing plan that provides an annual contribution at the discretion of the Company, based upon a percentage of the participants’ annual paid compensation. In order to be eligible for contribution, the eligible employee must be employed by the Company on December 31 st Other Benefits The Company’s Other Benefits Plan covers substantially all of its current retired employees. Employees hired after March 31, 2007 are not eligible to participate in this plan. Coverage includes healthcare and life insurance. Accrued retirement benefit costs are recorded each year. Regulatory Treatment of Over/Underfunded Retirement Obligations Because the Company is subject to regulation in the states in which it operates, it is required to maintain its accounts in accordance with the regulatory authority’s rules and guidelines, which may differ from other authoritative accounting pronouncements. In those instances, the Company follows the guidance of ASC 980, Regulated Operations Regulated Operations Compensation – Retirement Benefits The Company uses a December 31 measurement date for all of its employee benefit plans. The tables below set forth information relating to the Company’s Pension Plan and Other Benefits Plan for 2020 and 2019. ( Thousands of Dollars) Pension Plan Other Benefits Plan December 31, 2020 2019 2020 2019 Change in Projected Benefit Obligation: Beginning Balance $ 100,891 $ 83,927 $ 55,166 $ 48,474 Service Cost 2,434 2,171 993 839 Interest Cost 3,099 3,426 1,699 1,984 Actuarial (Gain) Loss 12,585 14,188 (4,279 ) 4,671 Benefits Paid (3,148 ) (2,821 ) (803 ) (802 ) Ending Balance $ 115,861 $ 100,891 $ 52,776 $ 55,166 60 Index ( Thousands of Dollars) Pension Plan Other Benefits Plan December 31, 2020 2019 2020 2019 Change in Fair Value of Plan Assets: Beginning Balance $ 80,380 $ 66,771 $ 40,613 $ 34,622 Actual Return on Plan Assets 8,289 12,753 3,988 5,192 Employer Contributions 3,400 3,677 1,094 1,601 Benefits Paid (3,148 ) (2,821 ) (803 ) (802 ) Ending Balance $ 88,921 $ 80,380 $ 44,892 $ 40,613 Funded Status $ (26,940 ) $ (20,511 ) $ (7,884 ) $ (14,553 ) ( Thousands of Dollars) Pension Plan Other Benefits Plan December 31, 2020 2019 2020 2019 Amounts Recognized in the Consolidated Balance Sheets consist of : Current Liability $ 398 $ 393 $ — $ — Noncurrent Liability 26,542 20,118 7,884 14,553 Net Liability Recognized $ 26,940 $ 20,511 $ 7,884 $ 14,553 (Thousands of Dollars) Pension Plan Other Benefits Plan Years Ended December 31, 2020 2019 2018 2020 2019 2018 Components of Net Periodic Benefit Cost Service Cost $ 2,434 $ 2,171 $ 2,426 $ 993 $ 839 $ 1,135 Interest Cost 3,099 3,426 3,061 1,699 1,984 1,898 Expected Return on Plan Assets (5,635 ) (4,694 ) (4,871 ) (2,853 ) (2,451 ) (2,550 ) Amortization of Net Actuarial Loss 2,059 1,618 1,658 1,352 1,319 1,787 Amortization of Prior Service Credit — — — — — (1,607 ) Net Periodic Benefit Cost* $ 1,957 $ 2,521 $ 2,274 $ 1,191 $ 1,691 $ 663 *Service cost is included in Operations and Maintenance expense on the consolidated statements of income; all other amounts are included in Other Income (Expense), net. Amounts that are expected to be amortized from Regulatory Assets into Net Periodic Benefit Cost in 2021 are as follows: (Thousands of Dollars) Pension Plan Other Benefits Plan Actuarial Loss $ 2,868 $ 527 61 Index The discount rate and compensation increase rate for determining our postretirement benefit plans’ benefit obligations and costs as of and for the years ended December 31, 2020, 2019 and 2018, respectively, are as follows: Pension Plan Other Benefits Plan Pension Plan Other Benefits Plan 2020 2019 2018 2020 2019 2018 Weighted Average Assumptions: Expected Return on Plan Assets 7.00 % 7.00 % 7.00 % 7.00 % 7.00 % 7.00 % Discount Rate for: Benefit Obligation 2.37 % 3.12 % 4.15 % 2.37 % 3.12 % 4.15 % Benefit Cost 3.12 % 4.15 % 3.53 % 3.12 % 4.15 % 3.53 % Compensation Increase for: Benefit Obligation 3.00 % 3.00 % 3.00 % 3.00 % 3.00 % 3.00 % Benefit Cost 3.00 % 3.00 % 3.00 % 3.00 % 3.00 % 3.00 % The compensation increase assumption for the Other Benefits Plan is attributable to life insurance provided to qualifying employees upon their retirement. The insurance coverage will be determined based on the employee’s base compensation as of their retirement date. The Company utilizes the Society of Actuaries’ mortality table (Pri-2012) (Mortality Improvement Scale MP2020 for the 2020 valuation). For the 2020 valuation, costs and obligations for our Other Benefits Plan assumed a 7.5% annual rate of increase in the per capita cost of covered healthcare benefits in 2021 with the annual rate of increase declining 0.5% per year for 2022-2027, resulting in an annual rate of increase in the per capita cost of covered healthcare benefits of 4.5% by year 2027. A one-percentage point change in assumed healthcare cost trend rates would have the following effects on the Other Benefits Plan: (Thousands of Dollars) 1 Percentage Point Increase Decrease Effect on Current Year Service and Interest Costs $ 561 $ (431 ) Effect on Projected Benefit Obligation $ 8,845 $ (6,941 ) The following benefit payments, which reflect expected future service, are expected to be paid: (Thousands of Dollars) Year Pension Plan Other Benefits Plan 2021 $ 3,373 $ 1,245 2022 3,537 1,489 2023 3,819 1,585 2024 4,715 1,664 2025 5,137 1,755 2026-2030 26,787 9,671 Totals $ 47,368 $ 17,409 62 Index Benefit Plans Assets The allocation of plan assets at December 31, 2020 and 2019 by asset category is as follows: Pension Plan Other Benefits Plan Asset Category 2020 2019 Target 2020 2019 Target Equity Securities 60.6 % 61.5 % 55 % 62.3 % 60.0 % 43 % Debt Securities 37.5 % 36.5 % 38 % 31.0 % 33.0 % 50 % Cash 1.2 % 0.5 % 2 % 6.7 % 7.0 % 2 % Real Estate/Commodities 0.7 % 1.5 % 5 % 0.0 % 0.0 % 5 % Total 100.0 % 100.0 % 100.0 % 100.0 % Two outside investment firms each manage a portion of the Pension Plan asset portfolio. One of those investment firms also manages the Other Benefits Plan asset portfolio. Quarterly meetings are held between the Company’s Pension Committee of the Board of Directors and the investment managers to review their performance and asset allocation. If the actual asset allocation is outside the targeted range, the Pension Committee reviews current market conditions and advice provided by the investment managers to determine the appropriateness of rebalancing the portfolio. The objective of the Company is to maximize the long-term return on retirement plan assets, relative to a reasonable level of risk, maintain a diversified investment portfolio and maintain compliance with the Employee Retirement Income Security Act of 1974. The expected long-term rate of return is based on the various asset categories in which plan assets are invested and the current expectations and historical performance for these categories. Equity securities include Middlesex common stock in the amounts of $1.4 million (1.6% of total Pension Plan assets) and $1.2 million (1.6% of total Pension Plan assets) as of December 31, 2020 and 2019, respectively. Fair Value Measurements Accounting guidance provides a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are described as follows: • Level 1 – Inputs to the valuation methodology are unadjusted quoted market prices for identical assets or liabilities in accessible active markets. • Level 2 – Inputs to the valuation methodology that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. If the asset or liability has a specified contractual term, the Level 2 input must be observable for substantially the full term of the asset or liability. • Level 3 – Inputs to the valuation methodology are unobservable and significant to the fair value measurement. Certain investments in cash and cash equivalents, equity securities, and commodities are valued based on quoted market prices in active markets and are classified as Level 1 investments. Certain investments in cash and cash equivalents, equity securities and fixed income securities are valued using prices received from pricing vendors that utilize observable inputs and are therefore classified as Level 2 investments. 63 Index The following tables present Middlesex’s Pension Plan assets measured and recorded at fair value within the fair value hierarchy: (Thousands of Dollars) As of December 31, 2020 Level 1 Level 2 Level 3 Total Mutual Funds $ 76,026 $ — $ — $ 76,026 Money Market Funds 1,086 — — 1,086 Common Equity Securities 11,809 — — 11,809 Total Investments $ 88,921 $ — $ — $ 88,921 (Thousands of Dollars) As of December 31, 2019 Level 1 Level 2 Level 3 Total Mutual Funds $ 69,565 $ — $ — $ 69,565 Money Market Funds 397 — — 397 Common Equity Securities 10,418 — — 10,418 Total Investments $ 80,380 $ — $ — $ 80,380 The following tables present Middlesex’s Other Benefits Plan assets measured and recorded at fair value within the fair value hierarchy: (Thousands of Dollars) As of December 31, 2020 Level 1 Level 2 Level 3 Total Mutual Funds $ 27,408 $ — $ — $ 27,408 Money Market Funds 3,696 — — 3,696 Agency/US/State/Municipal Debt — 13,788 — 13,788 Total Investments $ 31,104 $ 13,788 $ — $ 44,892 (Thousands of Dollars) As of December 31, 2019 Level 1 Level 2 Level 3 Total Mutual Funds $ 24,361 $ — $ — $ 24,361 Money Market Funds 2,859 — — 2,859 Agency/US/State/Municipal Debt — 13,393 — 13,393 Total Investments $ 27,220 $ 13,393 $ — $ 40,613 Benefit Plans Contributions For the Pension Plan, Middlesex made total cash contributions of $3.4 million in 2020 and expects to make approximately $3.4 million of cash contributions in 2021. For the Other Benefits Plan, Middlesex made total cash contributions of $1.1 million in 2020 and expects to make approximately $0.8 million of cash contributions in 2021. 64 Index 401(k) Plan The Company maintains a 401(k) defined contribution plan, which covers substantially all employees with more than 1,000 hours of service. Under the terms of the Plan, the Company matches 100% of a participant’s contributions, which do not exceed 1% of a participant’s compensation, plus 50% of a participant’s contributions exceeding 1%, but not more than 6%. The Company’s matching contribution was $0.7 million, $0.7 million and $0.6 million for the years ended December 31, 2020, 2019 and 2018, respectively. For those employees hired after March 31, 2007, who are not eligible to participate in the Pension Plan, and who are still actively employed on December 31, 2020, the Company will fund a discretionary contribution of $0.7 million which represents 5.0% of eligible 2020 compensation . For the years ended December 31, 2019 and 2018, the Company made discretionary contributions of $0.7 million and $0.6 million, respectively, for qualifying employees. Stock-Based Compensation The Company maintains a long-term incentive compensation plan where awards are made in the form of restricted common stock for certain management employees (the 2018 Restricted Stock Plan). Shares of restricted stock issued in connection with the 2018 Restricted Stock Plan are subject to forfeiture by the employee in the event of termination of employment for any reason within five years of the award other than as a result of retirement at normal retirement age, death, disability or change in control. The maximum number of shares authorized for grant under the 2018 Restricted Stock Plan is 300,000 shares, of which approximately 89% remain available for award. The Company recognizes compensation expense at fair value for the 2018 Restricted Stock Plan awards in accordance with ASC 718, Compensation – Stock Compensation The following table presents awarded but not yet vested share information for the 2018 Restricted Stock Plan: Shares (thousands) Unearned Compensation (thousands) Weighted Average Grant Price Balance, January 1, 2018 132 $ 1,785 Granted 22 827 $ 36.53 Vested (27 ) — Forfeited (2 ) (18 ) Amortization of Compensation Expense — (956 ) Balance, December 31, 2018 125 $ 1,638 Granted 18 975 $ 55.99 Vested (28 ) — Forfeited (18 ) — Amortization of Compensation Expense — (907 ) Balance, December 31, 2019 97 $ 1,706 Granted 16 982 $ 60.12 Vested (27 ) — Amortization of Compensation Expense — (851 ) Balance, December 31, 2020 86 $ 1,837 The fair value of vested restricted shares was $1.7 million as of both December 31, 2020 and 2019, respectively.

Business Segment Data

Business Segment Data	12 Months Ended
Business Segment Data	Dec. 31, 2020
Segment Reporting [Abstract]
Business Segment Data	Note 8 - Business Segment Data The Company has identified two reportable segments. One is the regulated business of collecting, treating and distributing water on a retail and wholesale basis to residential, commercial, industrial and fire protection customers in parts of New Jersey, Delaware and Pennsylvania. This segment also includes regulated wastewater systems in New Jersey and Delaware. The Company is subject to regulations as to its rates, services and other matters by the states of New Jersey, Delaware and Pennsylvania with respect to utility service within these states. The other segment is primarily comprised of non-regulated contract services for the operation and maintenance of municipal and private water and wastewater systems in New Jersey and Delaware. Inter-segment transactions relating to operational costs are treated as pass-through expenses. Finance charges on inter-segment loan activities are based on interest rates that are below what would normally be charged by a third party lender. (Thousands of Dollars) Years Ended December 31, Operations by Segments: 2020 2019 2018 Revenues: Regulated $ 129,851 $ 123,078 $ 121,901 Non – Regulated 12,545 12,177 16,778 Inter-segment Elimination (804 ) (657 ) (602 ) Consolidated Revenues $ 141,592 $ 134,598 $ 138,077 Operating Income: Regulated $ 34,043 $ 31,805 $ 34,127 Non – Regulated 3,377 3,715 3,015 Consolidated Operating Income $ 37,420 $ 35,520 $ 37,142 Depreciation: Regulated $ 18,264 $ 16,481 $ 14,846 Non – Regulated 208 235 191 Consolidated Depreciation $ 18,472 $ 16,716 $ 15,037 Other Income (Expense), Net: Regulated $ 4,605 $ 3,018 $ 3,284 Non – Regulated 130 (253 ) 119 Inter-segment Elimination (356 ) (273 ) (411 ) Consolidated Other Income (Expense), Net $ 4,379 $ 2,492 $ 2,992 Interest Charges: Regulated $ 7,780 $ 7,456 $ 7,060 Non – Regulated 70 81 109 Inter-segment Elimination (357 ) (273 ) (411 ) Consolidated Interest Charges $ 7,493 $ 7,264 $ 6,758 Income Taxes: Regulated $ (5,139 ) $ (4,317 ) $ (54 ) Non – Regulated 1,020 1,177 978 Consolidated Income Taxes $ (4,119 ) $ (3,140 ) $ 924 Net Income: Regulated $ 35,951 $ 31,602 $ 30,405 Non – Regulated 2,474 2,286 2,047 Consolidated Net Income $ 38,425 $ 33,888 $ 32,452 Capital Expenditures: Regulated $ 105,091 $ 88,858 $ 71,493 Non – Regulated 528 267 601 Total Capital Expenditures $ 105,619 $ 89,125 $ 72,094 66 Index (Thousands of Dollars) As of As of December 31, 2020 December 31, 2019 Assets: Regulated $ 998,932 $ 910,081 Non – Regulated 8,289 9,686 Inter-segment Elimination (30,751 ) (9,889 ) Consolidated Assets $ 976,470 $ 909,878

Quarterly Data - Unaudited

Quarterly Data - Unaudited	12 Months Ended
Quarterly Data - Unaudited	Dec. 31, 2020
Quarterly Financial Information Disclosure [Abstract]
Quarterly Data - Unaudited	Note 9 - Quarterly Data - Unaudited Financial information for each quarter of 2020 and 2019 is as follows: 2020 1 st 2 nd 3 rd 4 th Total Operating Revenues $ 31,769 $ 35,277 $ 39,920 $ 34,626 $ 141,592 Operating Income 6,527 9,385 13,177 8,331 37,420 Net Income 7,668 9,713 12,737 8,307 38,425 Basic Earnings per Share $ 0.44 $ 0.55 $ 0.73 $ 0.47 $ 2.19 Diluted Earnings per Share $ 0.44 $ 0.55 $ 0.72 $ 0.47 $ 2.18 Common Dividend Per Share $ 0.2563 $ 0.2563 $ 0.2563 $ 0.2725 $ 1.0414 High/Low Common Stock Price $ 69.92/$48.79 $ 72.41/$53.70 $ 69.89/$59.61 $ 76.08/$61.81 2019 1 st 2 nd 3 rd 4 th Total Operating Revenues $ 30,698 $ 33,393 $ 37,769 $ 32,738 $ 134,598 Operating Income 7,028 8,950 11,983 7,559 35,520 Net Income 6,552 8,146 11,119 8,071 33,888 Basic Earnings per Share $ 0.40 $ 0.49 $ 0.67 $ 0.46 $ 2.02 Diluted Earnings per Share $ 0.39 $ 0.49 $ 0.67 $ 0.46 $ 2.01 Common Dividend Per Share $ 0.2400 $ 0.2400 $ 0.2400 $ 0.2563 $ 0.9763 High/Low Common Stock Price $ 60.48/$51.02 $ 63.68/$52.51 $ 66.10/$55.30 $ 67.69/$58.75 The information above, in the opinion of the Company, includes all adjustments consisting only of normal recurring accruals necessary for a fair presentation of such amounts. The business of the Company is subject to seasonal fluctuation with the peak period usually occurring during the summer months. The quarterly earnings per share amounts above may differ slightly from previous filings due to the effects of rounding.

Organization, Summary of Sign_2

Organization, Summary of Significant Accounting Policies and Recent Developments (Policies)	12 Months Ended
	Dec. 31, 2020
Organization Summary Of Significant Accounting Policies And Recent Developments [Abstract]
Organization	(a) Organization Middlesex Water Company has operated as a water utility in New Jersey since 1897 and in Delaware, through our wholly-owned subsidiary, Tidewater, since 1992. We are in the business of collecting, treating, distributing and selling water for domestic, commercial, municipal, industrial and fire protection purposes. We also operate New Jersey municipal water, wastewater and storm water systems under contract and provide unregulated water and wastewater services in New Jersey and Delaware through our subsidiaries. Our rates charged to customers for water and wastewater services, the quality of services we provide and certain other matters are regulated in New Jersey, Delaware and Pennsylvania by the New Jersey Board of Public Utilities (NJBPU), Delaware Public Service Commission (DEPSC) and Pennsylvania Public Utilities Commission (PAPUC), respectively. Our USA, USA-PA and White Marsh subsidiaries are not regulated utilities.
Principles of Consolidation	(b) Principles of Consolidation -
System of Accounts	(c) System of Accounts -
Regulatory Accounting	(d) Regulatory Accounting Regulated Operations In accordance with ASC 980, Regulated Operations Rate and Regulatory Matters
Retirement Benefit Plans	(e) Retirement Benefit Plans 45 Index (Other Benefits Plan) for substantially all of its retired employees. Employees hired after March 31, 2007 are not eligible to participate in this plan. Coverage includes healthcare and life insurance. The Company’s costs for providing retirement benefits are dependent upon numerous factors, including actual plan experience and assumptions of future experience. Retirement benefit plan obligations and expense are determined based on investment performance, discount rates and various other demographic factors related to the population participating in the Company’s retirement benefit plans, all of which can change significantly in future years. For more information on the Company’s Retirement Benefit Plans, see Note 7 – Employee Benefit Plans
Utility Plant	(f) Utility Plant -
Depreciation	(g) Depreciation - Source of Supply 1.15% - 3.44% Transmission and Distribution (T&D): Pumping 2.00% - 5.39% T&D – Mains 1.10% - 3.13% Water Treatment 1.65% - 7.09% T&D – Services 2.12% - 3.16% General Plant 2.08% - 17.84% T&D – Other 1.61% - 4.63% Wastewater Collection 1.42% - 1.81% Non-regulated fixed assets consist primarily of office buildings, furniture and fixtures, and transportation equipment. These assets are recorded at original cost and depreciation is calculated based on the estimated useful lives, ranging from 3 to 42 years.
Preliminary Survey and Investigation (PS&I) Costs	(h) Preliminary Survey and Investigation (PS&I) Costs -
Customers' Advances for Construction (CAC)	(i) Customers’ Advances for Construction (CAC) -
Contributions in Aid of Construction (CIAC)	Contributions in Aid of Construction (CIAC) CAC and CIAC are not depreciated in accordance with regulatory requirements. In addition, these amounts reduce the investment base for purposes of setting rates.
Allowance for Funds Used During Construction (AFUDC)	(j) Allowance for Funds Used During Construction (AFUDC) 2020 2019 2018 Middlesex 6.50% 6.50% 6.50% Tidewater 7.92% 7.92% 7.92%
Accounts Receivable	(k) Accounts Receivable Note 1 (s), COVID-19
Revenues	(l) Revenues The Company’s regulated revenue from contracts with customers is derived from tariff-based sales that result from the obligation to provide water and wastewater services to residential, industrial, commercial, fire-protection and wholesale customers. The Company’s residential customers are billed quarterly while most of the Company’s industrial, commercial, fire-protection and wholesale customers are billed monthly. Payments by customers are due between 15 to 30 days after the invoice date. The Company recognizes revenue as the water and wastewater services are delivered to customers as well as records unbilled revenues estimated from the last meter reading date to the end of the accounting period utilizing factors such as historical customer data, regional weather indicators and general economic conditions in its service territories. Unearned Revenues and Advance Service Fees include fixed service charge billings in advance to Tidewater customers that are recognized as service is provided to the customer. Non-regulated service contract revenues consist of base service fees as well as fees for additional billable services provided to customers. Fees are billed monthly and are due within 30 days after the invoice date. The Company considers the amounts billed to represent the value of these services provided to customers. These contracts expire at various times through June 2030 and contain remaining performance obligations for which the Company expects to recognize revenue in the future. These contracts also contain customary termination provisions. Almost all of the amounts included in operating revenues and accounts receivable are from contracts with customers. The Company records its allowance for doubtful accounts based on historical write-offs combined with an evaluation of current economic conditions within its service territories. The Company’s contracts do not contain any significant financing components. 47 Index The Company’s operating revenues are comprised of the following: (In Thousands) Years Ended December 31, 2020 2019 2018 Regulated Tariff Sales Residential $ 76,798 $ 71,487 $ 69,785 Commercial 15,448 15,198 14,844 Industrial 9,512 9,390 10,183 Fire Protection 12,374 12,291 12,099 Wholesale 15,187 14,319 14,655 Non-Regulated Contract Operations 12,130 11,773 16,374 Total Revenue from Contracts with Customers $ 141,449 $ 134,458 $ 137,940 Other Regulated Revenues 532 393 335 Other Non-Regulated Revenues 415 404 404 Inter-segment Elimination (804 ) (657 ) (602 ) Total Revenue $ 141,592 $ 134,598 $ 138,077
Unamortized Debt Expense and Premiums on Long-Term Debt	(m) Unamortized Debt Expense and Premiums on Long-Term Debt
Income Taxes	(n) Income Taxes Income Taxes
Cash and Cash Equivalents	(o) Cash and Cash Equivalents
Restricted Cash	(p) Restricted Cash
Use of Estimates	(q) Use of Estimates
Recent Accounting Pronouncements	(r) Recent Accounting Pronouncements Leases - Leases Note 4 – Commitments and Contingent Liabilities 48 Index Credit Losses on Financial Instruments - Expected credit losses on accounts receivable and unbilled revenues are based on historical write-offs combined with an evaluation of current conditions and reasonable and supportable forecasts. Customer accounts are written off when collection efforts have been exhausted. There are no other new adopted or proposed accounting guidance that the Company is aware of that could have a material impact on the Company’s consolidated financial statements.
COVID-19	(s) COVID-19 The NJBPU and the DEPSC have allowed for potential future recovery of COVID-19 related incremental costs through customer rates by the regulated utilities under their respective jurisdictions. Neither jurisdiction has yet to establish a timetable or definitive formal procedures for seeking cost recovery. We will continue to monitor the COVID-19 situation and evaluate its impact on the Company’s business, results of operations, financial condition and liquidity.

Organization, Summary of Sign_3

Organization, Summary of Significant Accounting Policies and Recent Developments (Tables)	12 Months Ended
	Dec. 31, 2020
Organization Summary Of Significant Accounting Policies And Recent Developments [Abstract]
Range of depreciation rates	Source of Supply 1.15% - 3.44% Transmission and Distribution (T&D): Pumping 2.00% - 5.39% T&D – Mains 1.10% - 3.13% Water Treatment 1.65% - 7.09% T&D – Services 2.12% - 3.16% General Plant 2.08% - 17.84% T&D – Other 1.61% - 4.63% Wastewater Collection 1.42% - 1.81%
Allowance for Funds Used During Construction Rates	2020 2019 2018 Middlesex 6.50% 6.50% 6.50% Tidewater 7.92% 7.92% 7.92%
Schedule of Operating Revenues	(In Thousands) Years Ended December 31, 2020 2019 2018 Regulated Tariff Sales Residential $ 76,798 $ 71,487 $ 69,785 Commercial 15,448 15,198 14,844 Industrial 9,512 9,390 10,183 Fire Protection 12,374 12,291 12,099 Wholesale 15,187 14,319 14,655 Non-Regulated Contract Operations 12,130 11,773 16,374 Total Revenue from Contracts with Customers $ 141,449 $ 134,458 $ 137,940 Other Regulated Revenues 532 393 335 Other Non-Regulated Revenues 415 404 404 Inter-segment Elimination (804 ) (657 ) (602 ) Total Revenue $ 141,592 $ 134,598 $ 138,077

Rate and Regulatory Matters (Ta

Rate and Regulatory Matters (Tables)	12 Months Ended
Rate and Regulatory Matters (Tables)	Dec. 31, 2020
Regulated Operations [Abstract]
Schedule of regulatory assets	We have recorded certain costs as regulatory assets because we expect full recovery of, or are currently recovering, these costs in the rates we charge customers. These deferred costs have been excluded from rate base and, therefore, we are not earning a return on the unamortized balances. These items are detailed as follows: (Thousands of Dollars) December 31, Remaining Regulatory Assets 2020 2019 Recovery Periods Retirement Benefits $ 45,419 $ 44,281 Various Income Taxes 66,759 60,151 Various Rate Cases, Tank Painting, and Other 5,966 6,047 2-10 years Total $ 118,144 $ 110,479

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
Income Taxes (Tables)	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Income tax expense reconciliation	Income tax (benefit) expense is comprised of the following: (Thousands of Dollars) Years Ended December 31, 2020 2019 2018 Current: Federal $ (4,281 ) $ (3,822 ) $ (188 ) State 2,598 2,246 2,073 Deferred: Federal (1,490 ) (726 ) (338 ) State (871 ) (761 ) (545 ) Investment Tax Credits (75 ) (77 ) (78 ) Total Income Tax (Benefit) Expense $ (4,119 ) $ (3,140 ) $ 924
Income tax expense	Income tax (benefit) expense differs from the amount computed by applying the statutory rate on book income subject to tax for the following reasons: (Thousands of Dollars) Years Ended December 31, 2020 2019 2018 Income Tax at Statutory Rate $ 7,204 $ 6,457 $ 7,009 Tax Effect of: Utility Plant Related (1,356 ) (802 ) 422 Tangible Property Repairs (11,298 ) (10,156 ) (7,763 ) State Income Taxes – Net 1,364 1,173 1,207 Other (33 ) 188 49 Total Income Tax (Benefit) Expense $ (4,119 ) $ (3,140 ) $ 924
Deferred tax liability	Deferred income taxes reflect the net tax effect of temporary differences between the carrying amounts of assets and liabilities for financial purposes and the amounts used for income tax purposes. The components of the net deferred tax liability are as follows: (Thousands of Dollars) December 31, 2020 2019 Utility Plant Related $ 56,868 $ 50,608 Customer Advances (3,626 ) (3,661 ) Employee Benefits 7,339 6,543 Investment Tax Credits 445 519 Other 271 399 Total Accumulated Deferred Income Taxes $ 61,297 $ 54,408

Commitments and Contingent Li_2

Commitments and Contingent Liabilities (Tables)	12 Months Ended
Commitments and Contingent Liabilities (Tables)	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Schedule of water cost purchased	Purchased water costs are shown below: (Millions of Dollars) Years Ended December 31, 2020 2019 2018 Untreated $ 3.4 $ 3.4 $ 3.6 Treated 3.6 3.2 3.2 Total Costs $ 7.0 $ 6.6 $ 6.8
Schedule of operating lease ROU assets and lease liabilities	The Company’s future minimum operating lease commitments as of December 31, 2020 are as follows: (In Millions) December 31, 2020 2021 0.8 2022 0.8 2023 0.8 2024 0.8 2025 0.8 Thereafter 3.6 Total Lease Payments $ 7.6 Imputed Interest (1.9 ) Present Value of Lease Payments 5.7 Less Current Portion* (0.7 ) Non-Current Lease Liability $ 5.0 * Included in Other Current Liabilities
Schedule of future minimum operating lease	Information related to operating lease ROU assets is as follows: (In Millions December 31, 2020 2019 ROU Asset at Least Inception $ 7.3 $ 7.3 Accumulated Amortization (2.1 ) (1.4 ) Current ROU Asset $ 5.2 $ 5.9

Short-Term Borrowings (Tables)

Short-Term Borrowings (Tables)	12 Months Ended
Short-Term Borrowings (Tables)	Dec. 31, 2020
Short-term Debt [Abstract]
Schedule of information regarding short-term borrowings	Information regarding the Company’s short-term borrowings for the years ended December 31, 2020 and 2019 is summarized below: (Millions of Dollars) 2020 2019 Average Amount Outstanding $ 28.3 $ 52.4 Weighted Average Interest Rate 1.55 % 3.33 % Notes Payable at Year-End $ 2.0 $ 20.0 Weighted Average Interest Rate at Year-End 1.04 % 2.86 %
Schedule of Line of Credit	The Company maintained lines of credit aggregating $140.0 million at December 31, 2020 and 2019. (Millions) As of December 31, 2020 Line of Credit Outstanding Available Maximum Credit Type Renewal Date Bank of America $ - $ 60.0 $ 60.0 Uncommitted January 28, 2021 PNC Bank 2.0 66.0 68.0 Committed January 31, 2022 CoBank - 12.0 12.0 Committed November 30, 2023 $ 2.0 $ 138.0 $ 140.0

Capitalization (Tables)

Capitalization (Tables)	12 Months Ended
Capitalization (Tables)	Dec. 31, 2020
CAPITALIZATION:
Schedule of maturities of long term debt	FMB Series RR, SS, 2019A, 2019B and 2020A are term bonds with single maturity dates subsequent to 2025. The aggregate annual principal repayment obligations for all long-term debt over the next five years are shown below: Year (Millions of Dollars) Annual Maturities 2021 $ 7.3 2022 $ 6.7 2023 $ 16.1 2024 $ 6.0 2025 $ 5.6
Schedule of earnings per share	The following table presents the calculation of basic and diluted earnings per share (EPS) for the years ended December 31, 2020, 2019 and 2018. Basic EPS is computed on the basis of the weighted average number of shares outstanding. Diluted EPS assumes the conversion of both the Convertible Preferred Stock $7.00 Series and $8.00 Series (fully converted into common stock in September 2019). (In Thousands, Except Per Share Amounts) 2020 2019 2018 Basic: Income Shares Income Shares Income Shares Net Income $ 38,425 17,459 $ 33,888 16,685 $ 32,452 16,384 Preferred Dividend (120 ) (132 ) (144 ) Earnings Applicable to Common Stock $ 38,305 17,459 $ 33,756 16,685 $ 32,308 16,384 Basic EPS $ 2.19 $ 2.02 $ 1.97 Diluted: Earnings Applicable to Common Stock $ 38,305 17,459 $ 33,756 16,685 $ 32,308 16,384 $7.00 Series Dividend 67 115 67 115 67 115 $8.00 Series Dividend - - 12 29 24 41 Adjusted Earnings Applicable to Common Stock $ 38,372 17,574 $ 33,835 16,829 $ 32,399 16,540 Diluted EPS $ 2.18 $ 2.01 $ 1.96
Schedule of carrying amount and estimated fair value of bonds	The following methods and assumptions were used by the Company in estimating its fair value disclosure for financial instruments for which it is practicable to estimate that value. The carrying amounts reflected in the consolidated balance sheets for cash and cash equivalents, accounts receivable, accounts payable and notes payable approximate their respective fair values due to the short-term maturities of these instruments. The fair value of First Mortgage and State Revolving Fund Bonds (collectively, the Bonds) issued by Middlesex is based on quoted market prices for similar issues. Under the fair value hierarchy, the fair value of cash and cash equivalents is classified as a Level 1 measurement and the fair value of notes payable and the Bonds in the table below are classified as Level 2 measurements. The carrying amount and fair value of the Bonds were as follows: (Thousands of Dollars) At December 31, 2020 2019 Carrying Fair Carrying Fair Amount Value Amount Value Bonds $ 147,667 $ 159,195 $ 151,361 $ 160,772

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	12 Months Ended
Employee Benefit Plans (Tables)	Dec. 31, 2020
Retirement Benefits [Abstract]
Change in projected benefit obligation and fair value of plan assets	The Company uses a December 31 measurement date for all of its employee benefit plans. The tables below set forth information relating to the Company’s Pension Plan and Other Benefits Plan for 2020 and 2019. ( Thousands of Dollars) Pension Plan Other Benefits Plan December 31, 2020 2019 2020 2019 Change in Projected Benefit Obligation: Beginning Balance $ 100,891 $ 83,927 $ 55,166 $ 48,474 Service Cost 2,434 2,171 993 839 Interest Cost 3,099 3,426 1,699 1,984 Actuarial (Gain) Loss 12,585 14,188 (4,279 ) 4,671 Benefits Paid (3,148 ) (2,821 ) (803 ) (802 ) Ending Balance $ 115,861 $ 100,891 $ 52,776 $ 55,166 60 Index ( Thousands of Dollars) Pension Plan Other Benefits Plan December 31, 2020 2019 2020 2019 Change in Fair Value of Plan Assets: Beginning Balance $ 80,380 $ 66,771 $ 40,613 $ 34,622 Actual Return on Plan Assets 8,289 12,753 3,988 5,192 Employer Contributions 3,400 3,677 1,094 1,601 Benefits Paid (3,148 ) (2,821 ) (803 ) (802 ) Ending Balance $ 88,921 $ 80,380 $ 44,892 $ 40,613 Funded Status $ (26,940 ) $ (20,511 ) $ (7,884 ) $ (14,553 )
Amounts recognized in balance sheet	( Thousands of Dollars) Pension Plan Other Benefits Plan December 31, 2020 2019 2020 2019 Amounts Recognized in the Consolidated Balance Sheets consist of : Current Liability $ 398 $ 393 $ — $ — Noncurrent Liability 26,542 20,118 7,884 14,553 Net Liability Recognized $ 26,940 $ 20,511 $ 7,884 $ 14,553
Components of net benefit cost	(Thousands of Dollars) Pension Plan Other Benefits Plan Years Ended December 31, 2020 2019 2018 2020 2019 2018 Components of Net Periodic Benefit Cost Service Cost $ 2,434 $ 2,171 $ 2,426 $ 993 $ 839 $ 1,135 Interest Cost 3,099 3,426 3,061 1,699 1,984 1,898 Expected Return on Plan Assets (5,635 ) (4,694 ) (4,871 ) (2,853 ) (2,451 ) (2,550 ) Amortization of Net Actuarial Loss 2,059 1,618 1,658 1,352 1,319 1,787 Amortization of Prior Service Credit — — — — — (1,607 ) Net Periodic Benefit Cost* $ 1,957 $ 2,521 $ 2,274 $ 1,191 $ 1,691 $ 663 *Service cost is included in Operations and Maintenance expense on the consolidated statements of income; all other amounts are included in Other Income (Expense), net.
Amounts expected to be amortized from regulatory assets	Amounts that are expected to be amortized from Regulatory Assets into Net Periodic Benefit Cost in 2021 are as follows: (Thousands of Dollars) Pension Plan Other Benefits Plan Actuarial Loss $ 2,868 $ 527
Discount and compensation rates	The discount rate and compensation increase rate for determining our postretirement benefit plans’ benefit obligations and costs as of and for the years ended December 31, 2020, 2019 and 2018, respectively, are as follows: Pension Plan Other Benefits Plan Pension Plan Other Benefits Plan 2020 2019 2018 2020 2019 2018 Weighted Average Assumptions: Expected Return on Plan Assets 7.00 % 7.00 % 7.00 % 7.00 % 7.00 % 7.00 % Discount Rate for: Benefit Obligation 2.37 % 3.12 % 4.15 % 2.37 % 3.12 % 4.15 % Benefit Cost 3.12 % 4.15 % 3.53 % 3.12 % 4.15 % 3.53 % Compensation Increase for: Benefit Obligation 3.00 % 3.00 % 3.00 % 3.00 % 3.00 % 3.00 % Benefit Cost 3.00 % 3.00 % 3.00 % 3.00 % 3.00 % 3.00 %
Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates	A one-percentage point change in assumed healthcare cost trend rates would have the following effects on the Other Benefits Plan: (Thousands of Dollars) 1 Percentage Point Increase Decrease Effect on Current Year Service and Interest Costs $ 561 $ (431 ) Effect on Projected Benefit Obligation $ 8,845 $ (6,941 )
Expected benefit payments	The following benefit payments, which reflect expected future service, are expected to be paid: (Thousands of Dollars) Year Pension Plan Other Benefits Plan 2021 $ 3,373 $ 1,245 2022 3,537 1,489 2023 3,819 1,585 2024 4,715 1,664 2025 5,137 1,755 2026-2030 26,787 9,671 Totals $ 47,368 $ 17,409
Allocation of plan assets	The allocation of plan assets at December 31, 2020 and 2019 by asset category is as follows: Pension Plan Other Benefits Plan Asset Category 2020 2019 Target 2020 2019 Target Equity Securities 60.6 % 61.5 % 55 % 62.3 % 60.0 % 43 % Debt Securities 37.5 % 36.5 % 38 % 31.0 % 33.0 % 50 % Cash 1.2 % 0.5 % 2 % 6.7 % 7.0 % 2 % Real Estate/Commodities 0.7 % 1.5 % 5 % 0.0 % 0.0 % 5 % Total 100.0 % 100.0 % 100.0 % 100.0 %
Fair value of plan assets	The following tables present Middlesex’s Pension Plan assets measured and recorded at fair value within the fair value hierarchy: (Thousands of Dollars) As of December 31, 2020 Level 1 Level 2 Level 3 Total Mutual Funds $ 76,026 $ — $ — $ 76,026 Money Market Funds 1,086 — — 1,086 Common Equity Securities 11,809 — — 11,809 Total Investments $ 88,921 $ — $ — $ 88,921 (Thousands of Dollars) As of December 31, 2019 Level 1 Level 2 Level 3 Total Mutual Funds $ 69,565 $ — $ — $ 69,565 Money Market Funds 397 — — 397 Common Equity Securities 10,418 — — 10,418 Total Investments $ 80,380 $ — $ — $ 80,380 The following tables present Middlesex’s Other Benefits Plan assets measured and recorded at fair value within the fair value hierarchy: (Thousands of Dollars) As of December 31, 2020 Level 1 Level 2 Level 3 Total Mutual Funds $ 27,408 $ — $ — $ 27,408 Money Market Funds 3,696 — — 3,696 Agency/US/State/Municipal Debt — 13,788 — 13,788 Total Investments $ 31,104 $ 13,788 $ — $ 44,892 (Thousands of Dollars) As of December 31, 2019 Level 1 Level 2 Level 3 Total Mutual Funds $ 24,361 $ — $ — $ 24,361 Money Market Funds 2,859 — — 2,859 Agency/US/State/Municipal Debt — 13,393 — 13,393 Total Investments $ 27,220 $ 13,393 $ — $ 40,613
Restricted stock plan	The following table presents awarded but not yet vested share information for the 2018 Restricted Stock Plan: Shares (thousands) Unearned Compensation (thousands) Weighted Average Grant Price Balance, January 1, 2018 132 $ 1,785 Granted 22 827 $ 36.53 Vested (27 ) — Forfeited (2 ) (18 ) Amortization of Compensation Expense — (956 ) Balance, December 31, 2018 125 $ 1,638 Granted 18 975 $ 55.99 Vested (28 ) — Forfeited (18 ) — Amortization of Compensation Expense — (907 ) Balance, December 31, 2019 97 $ 1,706 Granted 16 982 $ 60.12 Vested (27 ) — Amortization of Compensation Expense — (851 ) Balance, December 31, 2020 86 $ 1,837

Business Segment Data (Tables)

Business Segment Data (Tables)	12 Months Ended
Business Segment Data (Tables)	Dec. 31, 2020
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	Inter-segment transactions relating to operational costs are treated as pass-through expenses. Finance charges on inter-segment loan activities are based on interest rates that are below what would normally be charged by a third party lender. (Thousands of Dollars) Years Ended December 31, Operations by Segments: 2020 2019 2018 Revenues: Regulated $ 129,851 $ 123,078 $ 121,901 Non – Regulated 12,545 12,177 16,778 Inter-segment Elimination (804 ) (657 ) (602 ) Consolidated Revenues $ 141,592 $ 134,598 $ 138,077 Operating Income: Regulated $ 34,043 $ 31,805 $ 34,127 Non – Regulated 3,377 3,715 3,015 Consolidated Operating Income $ 37,420 $ 35,520 $ 37,142 Depreciation: Regulated $ 18,264 $ 16,481 $ 14,846 Non – Regulated 208 235 191 Consolidated Depreciation $ 18,472 $ 16,716 $ 15,037 Other Income (Expense), Net: Regulated $ 4,605 $ 3,018 $ 3,284 Non – Regulated 130 (253 ) 119 Inter-segment Elimination (356 ) (273 ) (411 ) Consolidated Other Income (Expense), Net $ 4,379 $ 2,492 $ 2,992 Interest Charges: Regulated $ 7,780 $ 7,456 $ 7,060 Non – Regulated 70 81 109 Inter-segment Elimination (357 ) (273 ) (411 ) Consolidated Interest Charges $ 7,493 $ 7,264 $ 6,758 Income Taxes: Regulated $ (5,139 ) $ (4,317 ) $ (54 ) Non – Regulated 1,020 1,177 978 Consolidated Income Taxes $ (4,119 ) $ (3,140 ) $ 924 Net Income: Regulated $ 35,951 $ 31,602 $ 30,405 Non – Regulated 2,474 2,286 2,047 Consolidated Net Income $ 38,425 $ 33,888 $ 32,452 Capital Expenditures: Regulated $ 105,091 $ 88,858 $ 71,493 Non – Regulated 528 267 601 Total Capital Expenditures $ 105,619 $ 89,125 $ 72,094 66 Index (Thousands of Dollars) As of As of December 31, 2020 December 31, 2019 Assets: Regulated $ 998,932 $ 910,081 Non – Regulated 8,289 9,686 Inter-segment Elimination (30,751 ) (9,889 ) Consolidated Assets $ 976,470 $ 909,878

Quarterly Data - Unaudited (Tab

Quarterly Data - Unaudited (Tables)	12 Months Ended
Quarterly Data - Unaudited (Tables)	Dec. 31, 2020
Quarterly Financial Information Disclosure [Abstract]
Quarterly financial information	Financial information for each quarter of 2020 and 2019 is as follows: 2020 1 st 2 nd 3 rd 4 th Total Operating Revenues $ 31,769 $ 35,277 $ 39,920 $ 34,626 $ 141,592 Operating Income 6,527 9,385 13,177 8,331 37,420 Net Income 7,668 9,713 12,737 8,307 38,425 Basic Earnings per Share $ 0.44 $ 0.55 $ 0.73 $ 0.47 $ 2.19 Diluted Earnings per Share $ 0.44 $ 0.55 $ 0.72 $ 0.47 $ 2.18 Common Dividend Per Share $ 0.2563 $ 0.2563 $ 0.2563 $ 0.2725 $ 1.0414 High/Low Common Stock Price $ 69.92/$48.79 $ 72.41/$53.70 $ 69.89/$59.61 $ 76.08/$61.81 2019 1 st 2 nd 3 rd 4 th Total Operating Revenues $ 30,698 $ 33,393 $ 37,769 $ 32,738 $ 134,598 Operating Income 7,028 8,950 11,983 7,559 35,520 Net Income 6,552 8,146 11,119 8,071 33,888 Basic Earnings per Share $ 0.40 $ 0.49 $ 0.67 $ 0.46 $ 2.02 Diluted Earnings per Share $ 0.39 $ 0.49 $ 0.67 $ 0.46 $ 2.01 Common Dividend Per Share $ 0.2400 $ 0.2400 $ 0.2400 $ 0.2563 $ 0.9763 High/Low Common Stock Price $ 60.48/$51.02 $ 63.68/$52.51 $ 66.10/$55.30 $ 67.69/$58.75

Organization, Summary of Sign_4

Organization, Summary of Significant Accounting Policies and Recent Developments (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Organization, Summary Of Significant Accounting Policies And Recent Developments [Line Items]
Percent voting interest	50.00%
Percent of operating revenues	91.00%
Percent of total assets	99.00%
Allowance for doubtful accounts	$ 2.1	$ 1.4
Bad debt expense	1.1	1	$ 0.8
Write-offs	0.5	$ 0.6	$ 0.7
Right-of-use asset	6.7
Lease liability	7.1
Regulatory assets	$ 0.4
Minimum [Member]
Organization, Summary Of Significant Accounting Policies And Recent Developments [Line Items]
Estimated useful lives of non-regulated fixed assets	3 years
Maximum [Member]
Organization, Summary Of Significant Accounting Policies And Recent Developments [Line Items]
Estimated useful lives of non-regulated fixed assets	42 years

Organization, Summary of Sign_5

Organization, Summary of Significant Accounting Policies and Recent Developments (Schedule of Depreciation Rates) (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Source of Supply [Member] \| Minimum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	1.15%	1.15%	1.15%
Source of Supply [Member] \| Maximum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	3.44%	3.44%	3.44%
Pumping [Member] \| Minimum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	2.00%	2.00%	2.00%
Pumping [Member] \| Maximum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	5.39%	5.39%	5.39%
Water Treatment [Member] \| Minimum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	1.65%	1.65%	1.65%
Water Treatment [Member] \| Maximum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	7.09%	7.09%	7.09%
General Plant [Member] \| Minimum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	2.08%	2.08%	2.08%
General Plant [Member] \| Maximum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	17.84%	17.84%	17.84%
Wastewater Collection [Member] \| Minimum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	1.42%	1.42%	1.42%
Wastewater Collection [Member] \| Maximum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	1.81%	1.81%	1.81%
T&D Mains [Member] \| Minimum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	1.10%	1.10%	1.10%
T&D Mains [Member] \| Maximum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	3.13%	3.13%	3.13%
T&D Services [Member] \| Minimum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	2.12%	2.12%	2.12%
T&D Services [Member] \| Maximum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	3.16%	3.16%	3.16%
T&D Other [Member] \| Minimum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	1.61%	1.61%	1.61%
T&D Other [Member] \| Maximum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	4.63%	4.63%	4.63%

Organization, Summary of Sign_6

Organization, Summary of Significant Accounting Policies and Recent Developments (Schedule of AFUDC Rates) (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Middlesex [Member]
Organization, Summary Of Significant Accounting Policies And Recent Developments [Line Items]
Allowance for Funds Used During Construction Rates	6.50%	6.50%	6.50%
Tidewater [Member]
Organization, Summary Of Significant Accounting Policies And Recent Developments [Line Items]
Allowance for Funds Used During Construction Rates	7.92%	7.92%	7.92%

Organization, Summary of Sign_7

Organization, Summary of Significant Accounting Policies and Recent Developments (Schedule of Operating Revenues) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Regulated Tariff Sales
Residential									$ 76,798	$ 71,487	$ 69,785
Commercial									15,448	15,198	14,844
Industrial									9,512	9,390	10,183
Fire Protection									12,374	12,291	12,099
Wholesale									15,187	14,319	14,655
Non-Regulated Contract Operations									12,130	11,773	16,374
Total Revenue from Contracts with Customers									141,449	134,458	137,940
Other Regulated Revenues									532	393	335
Other Non-Regulated Revenues									415	404	404
Inter-segment Elimination									(804)	(657)	(602)
Total Revenue	$ 34,626	$ 39,920	$ 35,277	$ 31,769	$ 32,738	$ 37,769	$ 33,393	$ 30,698	$ 141,592	$ 134,598	$ 138,077

Rate and Regulatory Matters (Na

Rate and Regulatory Matters (Narrative) (Details) $ in Thousands	Nov. 04, 2019USD ($)	Mar. 01, 2019	Nov. 30, 2020USD ($)	Mar. 31, 2020USD ($)	Nov. 30, 2019USD ($)Customer	Mar. 31, 2018USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Regulatory Liabilities [Line Items]
Corporate tax rate		3.35%
Regulatory liabilities							$ 31,000	$ 31,500
Deferred income tax benefits							$ (13,490)	(11,719)	$ (8,724)
Maximum [Member]
Regulatory Liabilities [Line Items]
Corporate tax rate							35.00%
Minimum [Member]
Regulatory Liabilities [Line Items]
Corporate tax rate							21.00%
Delaware Public Service Commission [Member]
Regulatory Liabilities [Line Items]
Percentage of consumer price index							3.00%
Maturity date							Dec. 31, 2029
Delaware Public Service Commission [Member] \| Tidewater [Member]
Regulatory Liabilities [Line Items]
Approved increase in annual operating revenues							$ 600
Number of customers \| Customer					1,000
Purchase of the wastewater utility assets					$ 18
New Jersey Board Of Public Utilities [Member] \| Middlesex [Member]
Regulatory Liabilities [Line Items]
Approved increase in annual operating revenues			$ 1,100			$ 5,500
Additional annual costs				$ 600
Base rate amount						$ 245,500
Return on equity						9.60%
Regulatory liabilities							14,900	$ 24,200
Deferred income tax benefits						$ 28,700
Amortization period						4 years
New Jersey Board Of Public Utilities [Member] \| Pinelands Wastewater [Member]
Regulatory Liabilities [Line Items]
Approved increase in annual operating revenues	$ 500
Pennsylvania Public Utilities Commissio [Member] \| Twin Lakes [Member]
Regulatory Liabilities [Line Items]
Base rate amount							1,500
Revenues							$ 200

Rate and Regulatory Matters (Sc

Rate and Regulatory Matters (Schedule of Regulatory Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Regulatory Assets [Line Items]
Regulatory Assets	$ 118,144	$ 110,479
Retirement Benefits [Member]
Regulatory Assets [Line Items]
Regulatory Assets	$ 45,419	$ 44,281
Remaining recovery period	Various	Various
Income Taxes [Member]
Regulatory Assets [Line Items]
Regulatory Assets	$ 66,759	$ 60,151
Remaining recovery period	Various	Various
Rate Cases, Tank Painting, and Other [Member]
Regulatory Assets [Line Items]
Regulatory Assets	$ 5,966	$ 6,047
Remaining recovery period	2-10 years	2-10 years

Income Taxes (Schedule of Incom

Income Taxes (Schedule of Income Tax Expense Reconciliation) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income Tax at Statutory Rate	$ 7,204	$ 6,457	$ 7,009
Tax Effect of:
Utility Plant Related	(1,356)	(802)	422
Tangible Property Repairs	(11,298)	(10,156)	(7,763)
State Income Taxes - Net	1,364	1,173	1,207
Other	(33)	188	49
Total Income Tax (Benefit) Expense	$ (4,119)	$ (3,140)	$ 924

Income Taxes (Schedule of Inc_2

Income Taxes (Schedule of Income Tax Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current:
Federal	$ (4,281)	$ (3,822)	$ (188)
State	2,598	2,246	2,073
Deferred:
Federal	(1,490)	(726)	(338)
State	(871)	(761)	(545)
Investment Tax Credits	(75)	(77)	(78)
Total Income Tax (Benefit) Expense	$ (4,119)	$ (3,140)	$ 924

Income Taxes (Schedule of Net D

Income Taxes (Schedule of Net Deferred Tax Liability) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Utility Plant Related	$ 56,868	$ 50,608
Customer Advances	(3,626)	(3,661)
Employee Benefits	7,339	6,543
Investment Tax Credits (ITC)	445	519
Other	271	399
Total Deferred Tax Liability and ITC	$ 61,297	$ 54,408

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating Loss Carryforwards [Line Items]
Income taxes Paid	$ (4,119)	$ (3,140)	$ 924
Tax Year 2014 Through 2017 [Member]
Operating Loss Carryforwards [Line Items]
Interest expense	100	100
Income taxes Paid	$ 500	$ 2,700

Commitments and Contingent Li_3

Commitments and Contingent Liabilities (Narrative) (Details) $ in Thousands, gal in Millions	12 Months Ended
	Dec. 31, 2020USD ($)gal	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Commitment And Contingencies [Line Items]
Guarant liabilty for AWM's performance	$ 0	$ 1,400
Budgeted construction cost for construction program, 2021	134,000
Budgeted construction cost for construction program, 2022	97,000
Budgeted construction cost for construction program, 2023	83,000
Rental expenses under operating leases	800	$ 700	$ 500
Estimated obligation expend	$ 19,000
Estimated incremental borrowing rate	4.03%
Lease maturity date	2030
NJ Water Supply Authority [Member]
Commitment And Contingencies [Line Items]
Purchase commitment expiration date of contract	Nov. 30, 2023
Water purchase per commitment \| gal	27
Regulated Water Authority [Member]
Commitment And Contingencies [Line Items]
Purchase commitment expiration date of contract	Feb. 27, 2026
Water purchase per commitment \| gal	3
City of Dover [Member]
Commitment And Contingencies [Line Items]
Water purchase per commitment \| gal	15

Commitments and Contingent Li_4

Commitments and Contingent Liabilities (Schedule of Purchased Water Costs) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Purchased Water
Untreated	$ 3.4	$ 3.4	$ 3.6
Treated	3.6	3.2	3.2
Total Costs	$ 7	$ 6.6	$ 6.8

Commitments and Contingent Li_5

Commitments and Contingent Liabilities (Schedule of Operating Lease ROU Assets and Lease Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
ROU Asset at Lease Inception	$ 7.3	$ 7.3
Accumulated Amortization	(2.1)	(1.4)
Current ROU Asset	$ 5.2	$ 5.9

Commitments and Contingent Li_6

Commitments and Contingent Liabilities (Schedule of Future Minimum Operating Lease) (Details) $ in Millions	Dec. 31, 2020USD ($)
Minimum Lease Payments, Sale Leaseback Transactions, Fiscal Year Maturity [Abstract]
2021	$ 0.8
2022	0.8
2023	0.8
2024	0.8
2025	0.8
Thereafter	3.6
Total Lease Payments	7.6
Imputed Interest	(1.9)
Present Value of Lease Payments	5.7
Less Current Portion	(0.7)	[1]
Non-Current Lease Liability	$ 5

[1]	Included in Other Current Liabilities

Short-term Borrowings (Narrativ

Short-term Borrowings (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Short-term Debt [Abstract]
Maximum Lines of credit	$ 140	$ 140
Lines of credit	110
Reduce line of credit	$ 30

Short Term Borrowings (Schedule

Short Term Borrowings (Schedule of Weighted Average Daily Amounts of Borrowings Outstanding) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Lines Of Credit Facility
Average Outstanding	$ 28.3	$ 52.4
Weighted Average Interest Rate	1.55%	3.33%
Notes Payable at Year-End	$ 2	$ 20
Weighted Average Interest Rate at Year-End	1.04%	2.86%

Short-term Borrowings (Schedule

Short-term Borrowings (Schedule of Line of Credit) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Line of Credit Facility [Line Items]
Outstanding	$ 2
Available	138
Maximum	140	$ 140
Bank of America [Member]
Line of Credit Facility [Line Items]
Outstanding
Available	60
Maximum	$ 60
Credit Type	Uncommitted
Renewal Date	Jan. 28, 2021
PNC Bank [Member]
Line of Credit Facility [Line Items]
Outstanding	$ 2
Available	66
Maximum	$ 68
Credit Type	Committed
Renewal Date	Jan. 31, 2022
CoBank [Member]
Line of Credit Facility [Line Items]
Outstanding
Available	12
Maximum	$ 12
Credit Type	Committed
Renewal Date	Nov. 30, 2023

Capitalization (Narrative) (Det

Capitalization (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands

1 Months Ended

12 Months Ended

Nov. 30, 2020

Nov. 30, 2019

May 31, 2019

Feb. 28, 2019

Dec. 31, 2020

Dec. 31, 2019

Dec. 31, 2018

Aug. 31, 2019

Apr. 30, 2019

Sep. 30, 2018

Aug. 31, 2018

Mar. 31, 2018

Schedule of Capitalization [Line Items]

Issuance of Common Stock

$ 43,700

Public offering, price per share

$ 60.50

Issuance of Common Stock in a public offering, shares

800,000

Issuance of shares under the DRP

$ 1,230

$ 12,738

$ 1,150

Additional Shares Authorized By SEC To Be Issued

400,000

Preferred Stock, Shares Authorized

120,000

Preferred Stock, Shares Outstanding

20,000

Convertible preferred stock converted, value

$ 350

Amount drawn

$ 50,316

78,967

22,076

Long-term debt

277,241

234,397

Deobligated principal payments

258

130

Other long term debt

129,600

83,000

Customer advances

$ 23,404

$ 23,905

Delaware State Revolving Fund [Member]

Schedule of Capitalization [Line Items]

Maximum borrowing amount

$ 900

All Long-term Debt [Member]

Schedule of Capitalization [Line Items]

Weighted average interest rate

3.02%

3.17%

First Mortgage Bonds - Series 2019A [Member]

Schedule of Capitalization [Line Items]

Long-term debt

$ 32,500

Interest rate

4.00%

Maturity date

Aug. 1,
2059

First Mortgage Bonds - Series 2020A [Member]

Schedule of Capitalization [Line Items]

Long-term debt

$ 40,000

Interest rate

2.90%

Maturity date

Nov. 18,
2050

First Mortgage Bonds - Series 2019B [Member]

Schedule of Capitalization [Line Items]

Long-term debt

$ 21,200

Interest rate

5.00%

Maturity date

Aug. 1,
2059

Convertible Preferred Stock $7.00 Series [Member]

Schedule of Capitalization [Line Items]

Percentage of stock that may be redeemed in a given calander year

10.00%

Outside Director Stock Compensation Plan [Member]

Schedule of Capitalization [Line Items]

Common stock granted and issued under plan

4,074

3,521

4,004

Maximum number of shares authorized for grant

100,000

Preferred Stock, Shares Authorized

120,000

Preferred Stock, Shares Outstanding

31,000

New Jersey Infrastructure Bank [Member]

Schedule of Capitalization [Line Items]

Maximum borrowing capacity, construction loan

$ 8,700

$ 43,500

Percentage of principal with stated interest rate

75.00%

Percentage of principal with market interest rate

25.00%

Long-term debt

$ 89,100

Interest rate

0.00%

Construction Loan [Member]

Schedule of Capitalization [Line Items]

Interest rate

0.00%

New Jersey Board of Public Utilities (NJBPU) [Member]

Schedule of Capitalization [Line Items]

Proceeds from issuance of first mortgage bond

$ 100,000

Maturity date

Dec. 31,
2023

New Jersey Economic Development Authority [Member]

Schedule of Capitalization [Line Items]

Proceeds from issuance of first mortgage bond

$ 140,000

Maturity date

Dec. 31,
2022

New Jersey Infrastructure Bank [Member]

Schedule of Capitalization [Line Items]

Amount drawn

$ 41,900

First Mortgage Bonds [Member]

Schedule of Capitalization [Line Items]

Maximum borrowing capacity, construction loan

60,800

$ 53,700

Amount drawn

55,100

Amount of drawn expected remaining

5,700

New Jersey Economic Development Authority [Member]

Schedule of Capitalization [Line Items]

Long-term debt

109,100

Delaware State Revolving Fund [Member]

Schedule of Capitalization [Line Items]

Maximum borrowing amount

$ 10,000

Maximum borrowing capacity, construction loan

$ 1,700

Long-term debt

8,400

Private placement loan [Member]

Schedule of Capitalization [Line Items]

Interest rate

2.90%

Maturity date

Nov. 30,
2050

Repayment of loan

$ 40,000

Amortizing Secured Notes [Member]

Schedule of Capitalization [Line Items]

Long-term debt

30,600

Series 2018A [Member]

Schedule of Capitalization [Line Items]

Proceeds from issuance of first mortgage bond

$ 7,100

Dividend Reinvestment and Common Stock Purchase Plan [Member]

Schedule of Capitalization [Line Items]

Issuance of Common Stock

$ 1,200

$ 12,700

Dividend Reinvestment & Common Stock Purchase Plan, cumulative shares

200,000

Capitalization (Schedule of Mat

Capitalization (Schedule of Maturities of Long-term Debt) (Details) $ in Millions	Dec. 31, 2020USD ($)
CAPITALIZATION:
2021	$ 7.3
2022	6.7
2023	16.1
2024	6
2025	$ 5.6

Capitalization (Schedule of Ear

Capitalization (Schedule of Earnings Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Basic:
Net Income	$ 8,307	$ 12,737	$ 9,713	$ 7,668	$ 8,071	$ 11,119	$ 8,146	$ 6,552	$ 38,425	$ 33,888	$ 32,452
Preferred Dividend									(120)	(132)	(144)
Earnings Applicable to Common Stock									$ 38,305	$ 33,756	$ 32,308
Weighted-average number of basic shares outstanding, shares									17,459	16,685	16,384
Basic EPS	$ 0.47	$ 0.73	$ 0.55	$ 0.44	$ 0.46	$ 0.67	$ 0.49	$ 0.40	$ 2.19	$ 2.02	$ 1.97
Diluted:
$7.00 Series Preferred Dividend									$ 67	$ 67	$ 67
$8.00 Series Preferred Dividend										12	24
Adjusted Earnings Applicable to Common Stock									$ 38,372	$ 33,835	$ 32,399
Incremental common shares attributable to $7.00 series preferred shares, shares									115	115	115
Incremental common shares attributable to $8.00 series preferred shares, shares										29	41
Weighted-average diluted shares outstanding, shares									17,574	16,829	16,540
Diluted EPS	$ 0.47	$ 0.72	$ 0.55	$ 0.44	$ 0.46	$ 0.67	$ 0.49	$ 0.39	$ 2.18	$ 2.01	$ 1.96

Capitalization (Schedule of Car

Capitalization (Schedule of Carrying Amount and Fair Value of Bonds) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Carrying amount [Member]
Bonds	$ 147,667	$ 151,361
Fair value [Member]
Bonds	$ 159,195	$ 160,772

Employee Benefit Plans (Narrati

Employee Benefit Plans (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation	$ 101.7	$ 87.6
Increase (decrease) in annual rate per capita cost of covered healthcare benefits, next year	7.50%
Increase (decrease) in annual rate per capita cost of covered healthcare benefits, 2022-2027	0.50%
Increase (decrease) in annual rate per capita cost of covered healthcare benefits, 2027	4.50%
Number of hours required to participate in contribution plan	1,000
Percent of participants contributions matched by company, below one percent of participants compensation	100.00%
Percent of participants contributions matched by company, above one percent of participants compensation	50.00%
Threshold percentage of participants compensation at which matching decreases	1.00%
Matching contributions, percent	6.00%
Matching contributions	$ 0.7	0.7	$ 0.6
Discretionary contributions, percent	5.00%
Discretionary contributions	$ 0.7	0.7	$ 0.6
Maximum number of shares authorized for grant	300,000
Fair value of vested restricted shares	$ 1.7	$ 1.7
Middlesex [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Allocation of plan assets	1.60%	1.60%
Common stock in plan, value	$ 1.4	$ 1.2
Pension Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Allocation of plan assets	100.00%	100.00%
Benfit plan, Cash contributions	$ 3.4
Pension Benefit Plan [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Allocation of plan assets	60.60%	61.50%
Pension Benefit Plan [Member] \| Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Benfit plan, Cash contributions		$ 3.4
Other Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Allocation of plan assets	100.00%	100.00%
Other Benefits Plan [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Allocation of plan assets	62.30%	60.00%
Other Benefits Plan [Member] \| Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Benfit plan, Cash contributions	$ 0.8	$ 1.1

Employee Benefit Plans (Schedul

Employee Benefit Plans (Schedule of Change in Projected Benefit Obligation) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Pension Benefit Plan [Member]
Change in Projected Benefit Obligation:
Beginning Balance	$ 100,891	$ 83,927
Service Cost	2,434	2,171	$ 2,426
Interest Cost	3,099	3,426	3,061
Actuarial (Gain) Loss	(12,585)	(14,188)
Benefits Paid	(3,148)	(2,821)
Ending Balance	115,861	100,891	83,927
Other Benefits Plan [Member]
Change in Projected Benefit Obligation:
Beginning Balance	55,166	48,474
Service Cost	993	839	1,135
Interest Cost	1,699	1,984	1,898
Actuarial (Gain) Loss	4,279	(4,671)
Benefits Paid	(803)	(802)
Ending Balance	$ 52,776	$ 55,166	$ 48,474

Employee Benefit Plans (Sched_2

Employee Benefit Plans (Schedule of Change in Fair Value of Plan Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Pension Benefit Plan [Member]
Change in Fair Value of Plan Assets:
Beginning Balance	$ 80,380	$ 66,771
Actual Return on Plan Assets	8,289	12,753
Employer Contributions	3,400	3,677
Benefits Paid	(3,148)	(2,821)
Ending Balance	88,921	80,380
Funded Status	(26,940)	(20,511)
Other Benefits Plan [Member]
Change in Fair Value of Plan Assets:
Beginning Balance	40,613	34,622
Actual Return on Plan Assets	3,988	5,192
Employer Contributions	1,094	1,601
Benefits Paid	(803)	(802)
Ending Balance	44,892	40,613
Funded Status	$ (7,884)	$ (14,553)

Employee Benefit Plans (Sched_3

Employee Benefit Plans (Schedule of Employee Benefit Plans Recognized in Balance Sheet) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Noncurrent Liability	$ 34,426	$ 34,671
Pension Benefit Plan [Member]
Current Liability	398	393
Noncurrent Liability	26,542	20,118
Net Liability Recognized	26,940	20,511
Other Benefits Plan [Member]
Current Liability
Noncurrent Liability	7,884	14,553
Net Liability Recognized	$ 7,884	$ 14,553

Employee Benefit Plans (Sched_4

Employee Benefit Plans (Schedule of Periodic Costs For Employee Retirement Benefit Plans) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Pension Benefit Plan [Member]
Periodic costs for employee retirement benefit plans
Service Cost		$ 2,434	$ 2,171	$ 2,426
Interest Cost		3,099	3,426	3,061
Expected Return on Plan Assets		(5,635)	(4,694)	(4,871)
Amortization of Net Actuarial Loss		2,059	1,618	1,658
Amortization of Prior Service Credit
Net Periodic Benefit Cost	[1]	1,957	2,521	2,274
Other Benefits Plan [Member]
Periodic costs for employee retirement benefit plans
Service Cost		993	839	1,135
Interest Cost		1,699	1,984	1,898
Expected Return on Plan Assets		(2,853)	(2,451)	(2,550)
Amortization of Net Actuarial Loss		1,352	1,319	1,787
Amortization of Prior Service Credit				(1,607)
Net Periodic Benefit Cost	[1]	$ 1,191	$ 1,691	$ 663

[1]	Service cost is included in Operations and Maintenance expense on the consolidated statements of income; all other amounts are included in Other Income (Expense), net.

Employee Benefit Plans (Sched_5

Employee Benefit Plans (Schedule of Amounts Expected to be Amortized from Regulatory Assets to Net Periodic Benefit Cost) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)
Pension Benefit Plan [Member]
Actuarial Loss	$ 2,868
Other Benefits Plan [Member]
Actuarial Loss	$ 527

Employee Benefit Plans (Sched_6

Employee Benefit Plans (Schedule of Discount and Compensation Rates) (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Pension Benefit Plan [Member]
Weighted Average Assumptions:
Expected Return on Plan Assets	7.00%	7.00%	7.00%
Discount Rate for:
Benefit Obligation	2.37%	3.12%	4.15%
Benefit Cost	3.12%	4.15%	3.53%
Compensation Increase for:
Benefit Obligation	3.00%	3.00%	3.00%
Benefit Cost	3.00%	3.00%	3.00%
Other Benefits Plan [Member]
Weighted Average Assumptions:
Expected Return on Plan Assets	7.00%	7.00%	7.00%
Discount Rate for:
Benefit Obligation	2.37%	3.12%	4.15%
Benefit Cost	3.12%	4.15%	3.53%
Compensation Increase for:
Benefit Obligation	3.00%	3.00%	3.00%
Benefit Cost	3.00%	3.00%	3.00%

Employee Benefit Plans (Sched_7

Employee Benefit Plans (Schedule of Effect of One-percentage Point Change in Assumed Health Care Cost Trend Rates) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)
Pension Benefit Plan [Member]
Effect on Current Year Service and Interest Cost - Increase	$ 561
Effect on Projected Benefit Obligation - Increase	8,845
Other Benefits Plan [Member]
Effect on Current Year Service and Interest Cost - Decrease	(431)
Effect on Projected Benefit Obligation - Decrease	$ (6,941)

Employee Benefit Plans (Sched_8

Employee Benefit Plans (Schedule of Expected Benefit Payments) (Details) $ in Thousands	Dec. 31, 2020USD ($)
Pension Benefit Plan [Member]
2021	$ 3,373
2022	3,537
2023	3,819
2024	4,715
2025	5,137
2026-2030	26,787
Totals	47,368
Other Benefits Plan [Member]
2021	1,245
2022	1,489
2023	1,585
2024	1,664
2025	1,755
2026-2030	9,671
Totals	$ 17,409

Employee Benefit Plans (Sched_9

Employee Benefit Plans (Schedule of Allocation of Plan Assets) (Details)	Dec. 31, 2020	Dec. 31, 2019
Pension Benefit Plan [Member]
Allocation of plan assets	100.00%	100.00%
Pension Benefit Plan [Member] \| Commodities [Member]
Allocation of plan assets	0.70%	1.50%
Target plan allocations	5.00%
Pension Benefit Plan [Member] \| Cash [Member]
Allocation of plan assets	1.20%	0.50%
Target plan allocations	2.00%
Pension Benefit Plan [Member] \| Debt Securities [Member]
Allocation of plan assets	37.50%	36.50%
Target plan allocations	38.00%
Pension Benefit Plan [Member] \| Equity Securities [Member]
Allocation of plan assets	60.60%	61.50%
Target plan allocations	55.00%
Other Benefits Plan [Member]
Allocation of plan assets	100.00%	100.00%
Other Benefits Plan [Member] \| Commodities [Member]
Allocation of plan assets	0.00%	0.00%
Target plan allocations	5.00%
Other Benefits Plan [Member] \| Cash [Member]
Allocation of plan assets	6.70%	7.00%
Target plan allocations	2.00%
Other Benefits Plan [Member] \| Debt Securities [Member]
Allocation of plan assets	31.00%	33.00%
Target plan allocations	50.00%
Other Benefits Plan [Member] \| Equity Securities [Member]
Allocation of plan assets	62.30%	60.00%
Target plan allocations	43.00%

Employee Benefit Plans (Sche_10

Employee Benefit Plans (Schedule of Fair Value of Pension Plan Assets) (Details) - Pension Benefit Plan [Member] - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Level 1 [Member]
Fair value of plan assets	$ 88,921	$ 80,380
Fair Value, Level 2 [Member]
Fair value of plan assets
Fair Value, Level 3 [Member]
Fair value of plan assets
Equity Securities [Member]
Fair value of plan assets	11,809	10,418
Equity Securities [Member] \| Fair Value, Level 3 [Member]
Fair value of plan assets
Mutual Funds [Member]
Fair value of plan assets	76,026	69,565
Mutual Funds [Member] \| Fair Value, Level 1 [Member]
Fair value of plan assets	76,026	69,565
Mutual Funds [Member] \| Fair Value, Level 2 [Member]
Fair value of plan assets
Mutual Funds [Member] \| Fair Value, Level 3 [Member]
Fair value of plan assets
Money Market Funds [Member]
Fair value of plan assets	1,086	397
Money Market Funds [Member] \| Fair Value, Level 1 [Member]
Fair value of plan assets	1,086	397
Money Market Funds [Member] \| Fair Value, Level 2 [Member]
Fair value of plan assets
Money Market Funds [Member] \| Fair Value, Level 3 [Member]
Fair value of plan assets
Equity Securities [Member] \| Fair Value, Level 1 [Member]
Fair value of plan assets	11,809	10,418
Equity Securities [Member] \| Fair Value, Level 2 [Member]
Fair value of plan assets

Employee Benefit Plans (Sche_11

Employee Benefit Plans (Schedule of Fair Value of Other Benefits Plan Assets) (Details) - Other Benefits Plan [Member] - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Level 1 [Member]
Fair value of plan assets	$ 31,104	$ 27,220
Fair Value, Level 2 [Member]
Fair value of plan assets	13,788	13,393
Fair Value, Level 3 [Member]
Fair value of plan assets
Debt Securities [Member]
Fair value of plan assets	13,788	13,393
Mutual Funds [Member]
Fair value of plan assets	27,408	24,361
Mutual Funds [Member] \| Fair Value, Level 1 [Member]
Fair value of plan assets	27,408	24,361
Mutual Funds [Member] \| Fair Value, Level 2 [Member]
Fair value of plan assets
Mutual Funds [Member] \| Fair Value, Level 3 [Member]
Fair value of plan assets
Money Market Funds [Member]
Fair value of plan assets	3,696	2,859
Money Market Funds [Member] \| Fair Value, Level 1 [Member]
Fair value of plan assets	3,696	2,859
Money Market Funds [Member] \| Fair Value, Level 2 [Member]
Fair value of plan assets
Money Market Funds [Member] \| Fair Value, Level 3 [Member]
Fair value of plan assets
Debt Securities [Member] \| Fair Value, Level 1 [Member]
Fair value of plan assets
Debt Securities [Member] \| Fair Value, Level 2 [Member]
Fair value of plan assets	13,788	13,393
Debt Securities [Member] \| Fair Value, Level 3 [Member]
Fair value of plan assets

Employee Benefit Plans (Sche_12

Employee Benefit Plans (Schedule of Restricted Stock Plan) (Details) - 2008 Restricted Stock Plan [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Shares
Balance	97	125	132
Granted	16	18	22
Vested	(27)	(28)	(27)
Forfeited		(18)	(2)
Amortization of Compensation Expense
Balance	86	97	125
Unearned compensation
Balance	$ 1,706	$ 1,638	$ 1,785
Granted	982	975	827
Vested
Forfeited			(18)
Amortization of Compensation Expense	(851)	(907)	(956)
Balance	$ 1,837	$ 1,706	$ 1,638
Weighted Average Grant Price
Granted	$ 60.12	$ 55.99	$ 36.53

Business Segment Data (Details)

Business Segment Data (Details) $ in Thousands	3 Months Ended								12 Months Ended
Business Segment Data (Details) $ in Thousands	Dec. 31, 2020USD ($)	Sep. 30, 2020USD ($)	Jun. 30, 2020USD ($)	Mar. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Sep. 30, 2019USD ($)	Jun. 30, 2019USD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments									2
Revenues	$ 34,626	$ 39,920	$ 35,277	$ 31,769	$ 32,738	$ 37,769	$ 33,393	$ 30,698	$ 141,592	$ 134,598	$ 138,077
Operating Income	8,331	13,177	9,385	6,527	7,559	11,983	8,950	7,028	37,420	35,520	37,142
Depreciation									18,472	16,716	15,037
Other Income (Expense), Net									4,379	2,492	2,992
Interest Expense									7,493	7,264	6,758
Income Taxes									(4,119)	(3,140)	924
Net Income	8,307	$ 12,737	$ 9,713	$ 7,668	8,071	$ 11,119	$ 8,146	$ 6,552	38,425	33,888	32,452
Capital Expenditures									105,619	89,125	72,094
Assets	976,470				909,878				976,470	909,878
Inter-segment Elimination [Member]
Segment Reporting Information [Line Items]
Revenues									(804)	(657)	(602)
Other Income (Expense), Net									(356)	(273)	(411)
Interest Expense									(357)	(273)	(411)
Assets	(30,751)				(9,889)				(30,751)	(9,889)
Regulated [Member]
Segment Reporting Information [Line Items]
Revenues									129,851	123,078	121,901
Operating Income									34,043	31,805	34,127
Depreciation									18,264	16,481	14,846
Other Income (Expense), Net									4,605	3,018	3,284
Interest Expense									7,780	7,456	7,060
Income Taxes									(5,139)	(4,317)	(54)
Net Income									35,951	31,602	30,405
Capital Expenditures									105,091	88,858	71,493
Assets	998,932				910,081				998,932	910,081
Non - Regulated [Member]
Segment Reporting Information [Line Items]
Revenues									12,545	12,177	16,778
Operating Income									3,377	3,715	3,015
Depreciation									208	235	191
Other Income (Expense), Net									130	(253)	119
Interest Expense									70	81	109
Income Taxes									1,020	1,177	978
Net Income									2,474	2,286	2,047
Capital Expenditures									528	267	$ 601
Assets	$ 8,289				$ 9,686				$ 8,289	$ 9,686

Quarterly Data - Unaudited (Det

Quarterly Data - Unaudited (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Operating Revenues	$ 34,626	$ 39,920	$ 35,277	$ 31,769	$ 32,738	$ 37,769	$ 33,393	$ 30,698	$ 141,592	$ 134,598	$ 138,077
Operating Income	8,331	13,177	9,385	6,527	7,559	11,983	8,950	7,028	37,420	35,520	37,142
Net Income	$ 8,307	$ 12,737	$ 9,713	$ 7,668	$ 8,071	$ 11,119	$ 8,146	$ 6,552	$ 38,425	$ 33,888	$ 32,452
Basic Earnings per Share	$ 0.47	$ 0.73	$ 0.55	$ 0.44	$ 0.46	$ 0.67	$ 0.49	$ 0.40	$ 2.19	$ 2.02	$ 1.97
Diluted Earnings per Share	0.47	0.72	0.55	0.44	0.46	0.67	0.49	0.39	2.18	2.01	1.96
Common divident per share	0.2725	0.2563	0.2563	0.2563	0.2563	0.2400	0.2400	0.2400	$ 1.041	$ 0.976	$ 0.911
High common stock price	76.08	69.89	72.41	69.92	67.69	66.10	63.68	60.48
Low common stock price	$ 61.81	$ 59.61	$ 53.70	$ 48.79	$ 58.75	$ 55.30	$ 52.51	$ 51.02