Atkore (ATKR) 10-Q1 Feb 242024 Q1 Quarterly reportFinancial data

Company Profile

Cover

Cover - shares	3 Months Ended
Cover - shares	Dec. 29, 2023	Jan. 26, 2024
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Dec. 29, 2023
Document Transition Report	false
Entity File Number	001-37793
Entity Registrant Name	Atkore Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	90-0631463
Entity Address, Address Line One	16100 South Lathrop Avenue
Entity Address, City or Town	Harvey
Entity Address, State or Province	IL
Entity Address, Postal Zip Code	60426
City Area Code	708
Local Phone Number	339-1610
Title of 12(b) Security	Common Stock, $.01 par value per share
Trading Symbol	ATKR
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		36,768,282
Entity Central Index Key	0001666138
Document Fiscal Year Focus	2024
Amendment Flag	false
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--09-30

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended
	Dec. 29, 2023	Dec. 30, 2022
Income Statement [Abstract]
Net sales	$ 798,481	$ 833,821
Cost of sales	507,941	499,468
Gross profit	290,540	334,353
Selling, general and administrative	100,615	89,977
Intangible asset amortization	14,467	12,796
Operating income	175,458	231,580
Interest expense, net	7,793	9,488
Other expense, net	12	41
Income before income taxes	167,653	222,051
Income tax expense	29,272	48,559
Net income	$ 138,381	$ 173,492
Net income per share
Basic (in dollars per share)	$ 3.66	$ 4.26
Diluted (in dollars per share)	$ 3.61	$ 4.20

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
	Dec. 29, 2023	Dec. 30, 2022
Statement of Comprehensive Income [Abstract]
Net income	$ 138,381	$ 173,492
Other comprehensive income, net of tax:
Change in foreign currency translation adjustment	9,727	11,262
Change in unrecognized loss related to pension benefit plans	53	62
Total other comprehensive income	9,780	11,324
Comprehensive income	$ 148,161	$ 184,816

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 29, 2023	Sep. 30, 2023
Current Assets:
Cash and cash equivalents	$ 380,922	$ 388,114
Accounts receivable, less allowance for current and expected credit losses of $6,265 and $5,179, respectively	517,634	559,854
Inventories, net	493,637	493,852
Prepaid expenses and other current assets	105,951	96,670
Total current assets	1,498,144	1,538,490
Property, plant and equipment, net	586,983	559,041
Intangible assets, net	381,205	394,372
Goodwill	312,960	311,106
Right-of-use assets, net	144,828	120,747
Deferred tax assets	569	546
Other long-term assets	10,703	10,707
Total Assets	2,935,392	2,935,009
Current Liabilities:
Accounts payable	248,261	292,734
Income tax payable	4,625	6,322
Accrued compensation and employee benefits	30,516	45,576
Customer liabilities	131,121	121,576
Lease obligations	17,883	16,230
Other current liabilities	72,951	82,166
Total current liabilities	505,357	564,604
Long-term debt	763,225	762,687
Long-term lease obligations	129,050	105,517
Deferred tax liabilities	21,284	22,346
Other long-term liabilities	14,131	11,736
Total Liabilities	1,433,047	1,466,890
Equity:
Common stock, $0.01 par value, 1,000,000,000 shares authorized, 36,905,528 and 37,317,893 shares issued and outstanding, respectively	370	374
Additional paid-in capital	490,238	506,783
Retained earnings	1,035,897	994,902
Accumulated other comprehensive loss	(24,160)	(33,940)
Total Equity	1,502,345	1,468,119
Total Liabilities and Equity	$ 2,935,392	$ 2,935,009

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 29, 2023	Sep. 30, 2023
Statement of Financial Position [Abstract]
Accounts receivable, allowance for current and expected credit losses	$ 6,265	$ 5,179
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	1,000,000,000	1,000,000,000
Common stock, shares issued (in shares)	36,905,528	37,317,893
Common stock, shares outstanding (in shares)	36,905,528	37,317,893

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Dec. 29, 2023	Dec. 30, 2022
Operating activities:
Net income	$ 138,381	$ 173,492
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	29,020	25,967
Deferred income taxes	(1,668)	3,275
Stock-based compensation	4,757	5,270
Amortization of right-of-use assets	6,140	3,538
Other non-cash adjustments to net income	2,074	1,410
Changes in operating assets and liabilities, net of effects from acquisitions
Accounts receivable	43,837	26,841
Inventories	2,015	11,565
Prepaid expenses and other current assets	(9,140)	(6,930)
Accounts payable	(42,014)	(48,826)
Accrued and other liabilities	(15,946)	(36,070)
Income taxes	(260)	38,787
Other, net	910	532
Net cash provided by operating activities	158,106	198,851
Investing activities:
Capital expenditures	(44,331)	(35,006)
Acquisition of businesses, net of cash acquired	(5,973)	(82,181)
Net cash used in investing activities	(50,304)	(117,187)
Financing activities:
Issuance of common stock, net of shares withheld for tax	(21,299)	(14,775)
Repurchase of common stock	(96,428)	(150,056)
Finance lease payments	(427)	0
Net cash used for financing activities	(118,154)	(164,831)
Effects of foreign exchange rate changes on cash and cash equivalents	3,160	2,243
Decrease in cash and cash equivalents	(7,192)	(80,924)
Cash and cash equivalents at beginning of period	388,114	388,751
Cash and cash equivalents at end of period	380,922	307,827
Supplementary Cash Flow information
Capital expenditures, not yet paid	5,030	7,227
Operating lease right-of-use assets obtained in exchange for lease liabilities	24,752	1,181
Acquisitions of businesses, not yet paid	$ 0	$ 14,125

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENT OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss
Balance at beginning of period (in shares) at Sep. 30, 2022		41,351
Balance at beginning of period at Sep. 30, 2022	$ 1,249,787	$ 415	$ (2,580)	$ 500,117	$ 801,981	$ (50,146)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	173,492				173,492
Other comprehensive income	11,324					11,324
Stock-based compensation	5,270			5,270
Issuance of common stock, net of shares withheld for tax (in shares)		200
Issuance of common stock, net of shares withheld for tax	(14,775)	$ 1		(14,776)
Repurchase of common stock (in shares)		(1,683)
Repurchase of common stock	(150,056)	$ (16)			(150,040)
Balance at end of period (in shares) at Dec. 30, 2022		39,868
Balance at end of period at Dec. 30, 2022	1,275,042	$ 400	(2,580)	490,611	825,433	(38,822)
Balance at beginning of period (in shares) at Sep. 30, 2023		37,317
Balance at beginning of period at Sep. 30, 2023	1,468,119	$ 375	0	506,783	994,901	(33,940)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	138,381				138,381
Other comprehensive income	9,780					9,780
Stock-based compensation	4,757			4,757
Issuance of common stock, net of shares withheld for tax (in shares)		309
Issuance of common stock, net of shares withheld for tax	(21,299)	$ 3		(21,302)
Repurchase of common stock (in shares)		(721)
Repurchase of common stock	(97,392)	$ (7)			(97,385)
Balance at end of period (in shares) at Dec. 29, 2023		36,905
Balance at end of period at Dec. 29, 2023	$ 1,502,345	$ 370	$ 0	$ 490,238	$ 1,035,897	$ (24,160)

BASIS OF PRESENTATION AND SUMMA

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Dec. 29, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	1. BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation Organization and Ownership Structure — Atkore Inc. (the “ Company ” , “ Atkore ” or “ AI ” ) is a leading manufacturer of Electrical products primarily for the non-residential construction and renovation markets and Safety & Infrastructure solutions for the construction and industrial markets. Atkore was incorporated in the State of Delaware on November 4, 2010 under the name Atkore International Group, Inc. As of December 20, 2022, Atkore was the sole stockholder of Atkore International Holdings Inc. ( “ AIH ” ), which in turn was the sole stockholder of Atkore International Inc. ("AII"). On December 28, 2022, AIH merged into AII, with AII being the surviving entity. Accordingly, Atkore is now the sole stockholder of AII. The Electrical segment manufactures high quality products used in the construction of electrical power systems including conduit, cable, and installation accessories. This segment serves contractors, in partnership with the electrical wholesale channel. The Safety & Infrastructure segment designs and manufactures solutions including metal framing, mechanical pipe, perimeter security, and cable management for the protection and reliability of critical infrastructure. These solutions are marketed to contractors, original equipment manufacturers and end users. Basis of Presentation — The accompanying unaudited condensed consolidated financial statements of the Company included herein have been prepared in accordance with accounting principles generally accepted in the United States of America ( “ GAAP ” ). These unaudited condensed consolidated financial statements have been prepared in accordance with the Company ’ s accounting policies and on the same basis as those financial statements included in the Company ’ s latest Annual Report on Form 10-K for the year ended September 30, 2023, filed with the U.S. Securities and Exchange Commission (the “ SEC ” ) on November 17, 2023, and should be read in conjunction with those consolidated financial statements and the notes thereto. Certain information and disclosures normally included in the Company ’ s annual financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to the rules and regulations of the SEC. The unaudited condensed consolidated financial statements include the assets and liabilities used in operating the Company ’ s business. All intercompany balances and transactions have been eliminated in consolidation. The results of companies acquired or disposed of are included in the unaudited condensed consolidated financial statements from the effective date of acquisition or up to the date of disposal. These statements include all adjustments (consisting of normal recurring adjustments) that the Company considered necessary to present a fair statement of its results of operations, financial position and cash flows. The results reported in these unaudited condensed consolidated financial statements should not be regarded as necessarily indicative of results that may be expected for the entire year. Fiscal Periods — The Company has a fiscal year that ends on September 30. The Company ’ s fiscal quarters typically end on the last Friday in December, March and June as it follows a 4-5-4 calendar. Use of Estimates — The preparation of the condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclose contingent assets and liabilities at the date of the condensed consolidated financial statements and report the associated amounts of revenues and expenses. Actual results could differ materially from these estimates. Recent Accounting Pronouncements A summary of recently adopted accounting guidance is as follows. Adoption dates are on the first day of the fiscal year indicated below, unless otherwise specified. ASU Description of ASU Impact to Atkore Adoption Date 2023-07 Segment Reporting (Topic 280); Improvements to Reportable Segment Disclosures The ASU requires companies to provide additional segment disclosures including disclosing title and position of the chief operating decision maker (“CODM”), disclosure of significant segment expenses provided to and reviewed by the CODM, and that public entities provide all annual disclosures about a reportable segment’s profit or loss and assets required by Topic 280 in interim periods. The Company will adopt the standard in the first quarter of fiscal 2025 and include the disclosures required by the ASU within the Segment Footnote. 2025

REVENUE FROM CONTRACTS WITH CUS

REVENUE FROM CONTRACTS WITH CUSTOMERS	3 Months Ended
REVENUE FROM CONTRACTS WITH CUSTOMERS	Dec. 29, 2023
Revenue from Contract with Customer [Abstract]
REVENUE FROM CONTRACTS WITH CUSTOMERS	2. REVENUE FROM CONTRACTS WITH CUSTOMERS The Company’s revenue arrangements primarily consist of a single performance obligation to transfer promised goods which is satisfied at a point in time when title, risks and rewards of ownership, and subsequently control have transferred to the customer. This generally occurs when the product is shipped to the customer, with an immaterial amount of transactions in which control transfers upon delivery. The Company primarily offers assurance-type standard warranties that do not represent separate performance obligations. Under the Inflation Reduction Act of 2022 (“IRA”), the Company is eligible for tax credits related to the manufacturing and selling of components used in the solar energy industry. These tax credits are transferable under the IRA when they meet certain criteria. When credits do not meet the transferability criteria, the benefit is recognized within income tax expense in accordance with ASC 740, “Income Taxes.” Beginning in fiscal 2024, the Company has concluded that the credits generated are transferable. As such, the benefit of the solar tax credits is recognized as a reduction of cost of sales. The Company has contractual arrangements with certain customers to transfer a portion of the tax credits or to otherwise provide a rebate based on an agreed-upon value of the tax credits generated. Pursuant to such contractual arrangements, if the tax credits will be transferred to the customer, the Company identifies two separate performance obligations: (1) transfer the promised goods; and (2) transfer of the defined portion of the tax credits earned. The Company allocates the total value of these transactions between the two performance obligations. As a result of this allocation, the Company recognizes a reduction to revenue, similar to a rebate. For arrangements with no transfer of tax credits there is only a single performance obligation to transfer the promised goods and a rebate is granted based on the agreed-upon value of the tax credits generated. The solar tax credit receivable is recorded in Prepaid Expenses and Other Current Assets and the liability to transfer the defined portion of the tax credits or the economic value is recorded in Customer Liabilities. For the three months ended December 29, 2023, the Company has recognized a reduction of revenue of $14,853 for the economic value of tax credits to be transferred and a benefit to cost of sales of $19,127. As of December 29, 2023, the Company has a liability of $29,310 for credits to be transferred or the value thereof and a solar tax credit receivable of $64,595. As of December 29, 2023, all activity related to the solar tax credits is within the Safety & Infrastructure segment. The Company has certain arrangements that require it to estimate at the time of sale the amounts of variable consideration that should not be recorded as revenue as certain amounts are not expected to be collected from customers, as well as an estimate of the value of products to be returned. The Company principally relies on historical experience, specific customer agreements, and anticipated future trends to estimate these amounts at the time of sale and to reduce the transaction price. These arrangements include sales discounts and allowances, volume rebates, and returned goods. The Company records its obligations related to these items within the Customer Liabilities line on the balance sheet. The Company records amounts billed to customers for reimbursement of shipping and handling costs within revenue. Shipping and handling costs associated with outbound freight after control over a product has transferred to a customer are accounted for as fulfillment costs and are included in cost of goods sold. Sales taxes and other usage-based taxes are excluded from revenue. The Company does not evaluate whether the selling price includes a financing interest component for contracts that are less than a year. The Company also expenses costs incurred to obtain a contract, primarily sales commissions, as all obligations will be settled in less than one year. The Company typically receives payment 30 to 60 days from the point it has satisfied the related performance obligation. See Note 16, “Segment Information” for revenue disaggregated by geography and product categories.

ACQUISITIONS

ACQUISITIONS	3 Months Ended
ACQUISITIONS	Dec. 29, 2023
Business Combination and Asset Acquisition [Abstract]
ACQUISITIONS	3. ACQUISITIONS From time to time, the Company enters into strategic acquisitions in an effort to better service existing customers and to obtain new customers. During the three months ended December 29, 2023, the Company paid out $5,973 of accrued purchase price related to the fiscal 2022 acquisition of Cascade Poly Pipe & Conduit and Northwest Polymers. No other acquisition activity occurred during the three months ended December 29, 2023. Fiscal 2023 On November 7, 2022, Atkore HDPE, LLC, a wholly-owned subsidiary of the Company, acquired the assets of Elite Polymer Solutions (“Elite”), for a purchase price of $90,230, of which $75,981 was paid at closing and an additional purchase price payable of $14,000 was accrued, of which $500 was paid in fiscal 2023 subsequent to the acquisition date. Elite is a manufacturer of high density polyethylene (HDPE) conduit, primarily serving the telecommunications, utility, and transportation markets. As a result of the acquisition, the Company preliminarily recognized $18,669 of tax deductible goodwill, $68,480 of identifiable intangible assets, of which $68,200 relates to customer relationships with an estimated useful life of 8 years, and $3,082 of working capital and other net tangible assets. The Company finalized the purchase price allocation of Elite in the fourth quarter of fiscal 2023. The Elite acquisition in fiscal 2023 was funded using cash-on-hand. The Company incurred approximately $968 in acquisition-related expenses for fiscal 2023, which was recorded as a component of selling, general and administrative expenses.

POSTRETIREMENT BENEFITS

POSTRETIREMENT BENEFITS	3 Months Ended
POSTRETIREMENT BENEFITS	Dec. 29, 2023
Retirement Benefits [Abstract]
POSTRETIREMENT BENEFITS	4. POSTRETIREMENT BENEFITS The Company provides pension benefits through a number of noncontributory and contributory defined benefit retirement plans covering eligible U.S. employees. As of September 30, 2017, all defined pension benefit plans were frozen, whereby participants no longer accrue credited service. The net periodic benefit credit was as follows: Three months ended (in thousands) Note December 29, 2023 December 30, 2022 Interest cost $ 1,316 $ 1,294 Expected return on plan assets (841) (1,257) Amortization of actuarial loss 67 167 Net periodic benefit cost 5 $ 542 $ 204

OTHER EXPENSE, NET

OTHER EXPENSE, NET	3 Months Ended
OTHER EXPENSE, NET	Dec. 29, 2023
Other Income and Expenses [Abstract]
OTHER EXPENSE, NET	5. OTHER EXPENSE, NET Other expense, net consisted of the following: Three months ended (in thousands) December 29, 2023 December 30, 2022 Undesignated foreign currency derivative instruments $ — $ (14) Loss on assets held for sale (64) — Foreign exchange loss on intercompany loans (198) (149) Pension-related benefits 274 204 Other expense, net $ 12 $ 41

INCOME TAXES

INCOME TAXES	3 Months Ended
INCOME TAXES	Dec. 29, 2023
Income Tax Disclosure [Abstract]
INCOME TAXES	6. INCOME TAXES For the three months ended December 29, 2023 and December 30, 2022, the Company’s effective tax rate attributable to income before income taxes was 17.5% and 21.9%, respectively. For the three months ended December 29, 2023 and December 30, 2022, the Company’s income tax expense was $29,272 and $48,559 respectively. The decrease in the current period effective tax rate was driven by an increase in the excess tax benefit associated with stock compensation.

EARNINGS PER SHARE

EARNINGS PER SHARE	3 Months Ended
EARNINGS PER SHARE	Dec. 29, 2023
Earnings Per Share [Abstract]
EARNINGS PER SHARE	7. EARNINGS PER SHARE The Company calculates basic and diluted earnings per common share using the two-class method. Under the two-class method, net earnings are allocated to each class of common stock and participating securities as if all of the net earnings for the period had been distributed. The Company ’ s participating securities consist of share-based payment awards that contain a non-forfeitable right to receive dividends and therefore are considered to participate in undistributed earnings with common stockholders. Basic earnings per common share excludes dilution and is calculated by dividing the net earnings allocated to common stock by the weighted-average number of common stock outstanding for the period. Diluted earnings per common share is calculated by dividing net earnings allocated to common stock by the weighted-average number of shares outstanding for the period, as adjusted for the potential dilutive effect of non-participating share-based awards. The following table sets forth the computation of basic and diluted earnings per share: Three months ended (in thousands, except per share data) December 29, 2023 December 30, 2022 Numerator: Net income $ 138,381 $ 173,492 Less: Undistributed earnings allocated to participating securities 2,072 2,807 Net income available to common shareholders $ 136,309 $ 170,685 Denominator: Basic weighted average common shares outstanding 37,242 40,085 Effect of dilutive securities: Non-participating employee stock options (1) 503 528 Diluted weighted average common shares outstanding 37,745 40,613 Basic earnings per share $ 3.66 $ 4.26 Diluted earnings per share $ 3.61 $ 4.20 (1) Stock options to purchase shares of common stock that would have been anti-dilutive are not included in the calculation. There were no anti-dilutive options outstanding during the three months ended December 29, 2023 and December 30, 2022.

ACCUMULATED OTHER COMPREHENSIVE

ACCUMULATED OTHER COMPREHENSIVE LOSS	3 Months Ended
ACCUMULATED OTHER COMPREHENSIVE LOSS	Dec. 29, 2023
Equity [Abstract]
ACCUMULATED OTHER COMPREHENSIVE LOSS	8. ACCUMULATED OTHER COMPREHENSIVE LOSS The following table presents the changes in accumulated other comprehensive loss by component for the three months ended December 29, 2023 and December 30, 2022. (in thousands) Defined Benefit Currency Total Balance as of September 30, 2023 $ (10,801) $ (23,139) $ (33,940) Other comprehensive income before reclassifications — 9,727 9,727 Amounts reclassified from accumulated other 53 — 53 Net current period other comprehensive income 53 9,727 9,780 Balance as of December 29, 2023 $ (10,748) $ (13,412) $ (24,160) (in thousands) Defined Benefit Currency Total Balance as of September 30, 2022 $ (16,795) $ (33,351) $ (50,146) Other comprehensive income before reclassifications — 11,262 11,262 Amounts reclassified from accumulated other 62 — 62 Net current period other comprehensive income 62 11,262 11,324 Balance as of December 30, 2022 $ (16,733) $ (22,089) $ (38,822)

INVENTORIES, NET

INVENTORIES, NET	3 Months Ended
INVENTORIES, NET	Dec. 29, 2023
Inventory Disclosure [Abstract]
INVENTORIES, NET	9. INVENTORIES, NET A majority of the Company ’ s inventories are recorded at the lower of cost (primarily last in, first out, or “ LIFO ” ) or market or net realizable value, as applicable. Approximately 86% and 82% of the Company ’ s inventories were valued at the lower of LIFO cost or market at December 29, 2023 and September 30, 2023, respectively. Interim LIFO determinations, including those at December 29, 2023, are based on management ’ s estimates of future inventory levels and costs for the remainder of the current fiscal year. (in thousands) December 29, 2023 September 30, 2023 Purchased materials and manufactured parts, net $ 194,417 $ 231,518 Work in process, net 61,993 60,524 Finished goods, net 237,227 201,810 Inventories, net $ 493,637 $ 493,852

PROPERTY, PLANT AND EQUIPMENT

PROPERTY, PLANT AND EQUIPMENT	3 Months Ended
PROPERTY, PLANT AND EQUIPMENT	Dec. 29, 2023
Property, Plant and Equipment [Abstract]
PROPERTY, PLANT AND EQUIPMENT	10. PROPERTY, PLANT AND EQUIPMENT As of December 29, 2023, and September 30, 2023, property, plant and equipment and accumulated depreciation were as follows: (in thousands) December 29, 2023 September 30, 2023 Land $ 29,357 $ 29,082 Buildings and related improvements 184,606 182,760 Machinery and equipment 524,607 513,563 Leasehold improvements 16,901 15,910 Software 46,807 47,072 Construction in progress 235,549 206,311 Property, plant and equipment, at cost 1,037,827 994,698 Accumulated depreciation (450,844) (435,657) Property, plant and equipment, net $ 586,983 $ 559,041

GOODWILL AND INTANGIBLE ASSETS

GOODWILL AND INTANGIBLE ASSETS	3 Months Ended
GOODWILL AND INTANGIBLE ASSETS	Dec. 29, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL AND INTANGIBLE ASSETS	11. GOODWILL AND INTANGIBLE ASSETS Changes in the carrying amount of goodwill are as follows: (in thousands) Electrical Safety & Infrastructure Total Balance as of September 30, 2023 $ 258,427 $ 52,679 $ 311,106 Exchange rate effects 1,667 187 1,854 Balance as of December 29, 2023 $ 260,094 $ 52,866 $ 312,960 Goodwill balances as of December 29, 2023 included $5,645 and $43,000 of accumulated impairment losses within the Electrical and Safety & Infrastructure segments, respectively. The Company assesses the recoverability of goodwill and indefinite-lived trade names on an annual basis in accordance with ASC 350, “ Intangibles - Goodwill and Other. ” The measurement date is the first day of the fourth fiscal quarter, or more frequently, if events or circumstances indicate that it is more likely than not that the fair value of a reporting unit or the respective indefinite-lived trade name is less than the carrying value. The following table provides the gross carrying value, accumulated amortization and net carrying value for each major class of intangible asset: December 29, 2023 September 30, 2023 (in thousands) Weighted Average Useful Life (Years) Gross Carrying Value Accumulated Amortization Net Carrying Value Gross Carrying Value Accumulated Amortization Net Carrying Value Amortizable intangible assets: Customer relationships 11 $ 596,522 $ (330,703) $ 265,819 $ 596,396 $ (318,058) $ 278,338 Other 8 46,259 (23,684) 22,575 43,633 (20,406) 23,227 Total 642,781 (354,387) 288,394 640,029 (338,464) 301,565 Indefinite-lived intangible assets: Trade names 92,811 — 92,811 92,806 — 92,806 Total $ 735,592 $ (354,387) $ 381,205 $ 732,835 $ (338,464) $ 394,372 Other intangible assets consist of definite-lived trade names, technology, non-compete agreements and backlogs. Included in the table above are the effects of changes in exchange rates which were not material for the three months ended December 29, 2023. Amortization expense for the three months ended December 29, 2023 and December 30, 2022 was $14,467 and $12,796, respectively. Expected amortization expense for intangible assets for the remainder of fiscal 2024 and over the next five years and thereafter is as follows: (in thousands) Remaining 2024 $ 41,242 2025 43,326 2026 40,726 2027 39,610 2028 29,445 2029 28,293 Thereafter 65,752 Actual amounts of amortization may differ from estimated amounts due to additional intangible asset acquisitions, impairment of intangible assets and other events.

DEBT

DEBT	3 Months Ended
DEBT	Dec. 29, 2023
Debt Disclosure [Abstract]
DEBT	12. DEBT Debt as of December 29, 2023 and September 30, 2023 was as follows: (in thousands) December 29, 2023 September 30, 2023 Senior Secured Term Loan Facility due May 26, 2028 $ 371,738 $ 371,667 Senior Notes due June 2031 400,000 400,000 Deferred financing costs (8,513) (8,980) Long-term debt $ 763,225 $ 762,687 The asset-based credit facility (the “ ABL Credit Facility ” ) has aggregate commitments of $325,000. AII is the borrower under the ABL Credit Facility which is guaranteed by the Company and all other subsidiaries of the Company (other than AII) that are guarantors of the Senior Notes. AII ’ s availability under the ABL Credit Facility was $322,406 as of December 29, 2023 and $322,406 as of September 30, 2023. The ABL Credit Facility will mature on the earlier of five years from May 26, 2021 or 91 days prior to the maturity date of the New Senior Secured Term Loan Facility if at least $100 million of obligations remain outstanding under the New Senior Secured Term Loan Facility on such date. The ABL Credit Facility uses a forward-looking interest rate based on the Secured Overnight Financing Rate (“SOFR”) consisting of an applicable margin ranging from 1.25% to 1.75% and a credit spread adjustment of 0.10%. The New Senior Secured Term Loan Facility will mature on May 26, 2028 and borrowings thereunder bearing interest at the rate of forward-looking interest rate based on the “SOFR”, consisting of an applicable margin of 2.00% and a credit spread adjustment of (i) 0.11448% for a one-month interest period, (ii) 0.26161% for a three-month interest period and (iii) 0.42826% for a six-month interest period. Senior Notes - On May 26, 2021, the Company completed the issuance and sale of the $400.0 million aggregate principal amount of 4.25% Senior Notes due 2031 (the “Senior Notes”) in a private offering. The Senior Notes were sold only to qualified institutional buyers in compliance with Rule 144A of the Securities Act of 1933, as amended (the “Securities Act”), and to non-U.S. persons outside of the United States in compliance with Regulation S of the Securities Act.

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	3 Months Ended
FAIR VALUE MEASUREMENTS	Dec. 29, 2023
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	13. FAIR VALUE MEASUREMENTS Certain assets and liabilities are required to be recorded at fair value on a recurring basis. The Company periodically uses forward currency contracts to hedge the effects of foreign exchange relating to intercompany balances denominated in a foreign currency. These derivative instruments are not formally designated as a hedge by the Company. Short-term forward currency contracts are recorded in either other current assets or other current liabilities and long-term forward currency contracts are recorded in either other long-term assets or other long-term liabilities in the condensed consolidated balance sheet. The fair value gains and losses are included in other expense, net within the condensed consolidated statements of operations. See Note 5, “Other Expense, net” for further detail. Cash flows associated with derivative financial instruments are recognized in the operating section of the condensed consolidated statements of cash flows. The fair value of forward currency contracts is calculated by reference to current forward exchange rates for contracts with similar maturity profiles. The Company had no active forward currency contracts or other derivative instruments as of December 29, 2023 or September 30, 2023. The following table presents the Company ’ s assets and liabilities measured at fair value: December 29, 2023 September 30, 2023 (in thousands) Level 1 Level 2 Level 1 Level 2 Assets Cash equivalents $ 298,683 $ — $ 321,282 $ — The Company ’ s remaining financial instruments consist primarily of cash, accounts receivable and accounts payable whose carrying value approximate their fair value due to their short-term nature. The estimated fair value of financial instruments not carried at fair value in the condensed consolidated balance sheets were as follows: December 29, 2023 September 30, 2023 (in thousands) Carrying Value Fair Value Carrying Value Fair Value Senior Secured Term Loan Facility due May 26, 2028 $ 373,000 $ 373,116 $ 373,000 $ 372,068 Senior Notes due June 2031 400,000 360,272 400,000 334,368 Total Debt $ 773,000 $ 733,388 $ 773,000 $ 706,436

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
COMMITMENTS AND CONTINGENCIES	Dec. 29, 2023
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	14. COMMITMENTS AND CONTINGENCIES The Company has obligations related to commitments to purchase certain goods. As of December 29, 2023, such obligations were $281,447 for the rest of fiscal year 2024 and $13,895 for fiscal year 2025 and beyond. These amounts represent open purchase orders for materials used in production. Insurable Liabilities — The Company maintains policies with various insurance companies for its workers’ compensation, product, property, general, auto, and executive liability risks. The insurance policies that the Company maintains have various retention levels and excess coverage limits. The establishment and update of liabilities for unpaid claims, including claims incurred but not reported, is based on management's estimate as a result of the assessment by the Company's claim administrator of each claim and an independent actuarial valuation of the nature and severity of total claims. The Company utilizes a third-party claims administrator to pay claims, track and evaluate actual claims experience, and ensure consistency in the data used in the actuarial valuation. Legal Contingencies — Historically, a number of lawsuits have been filed against the Company and the Company has also received other claim demand letters alleging that the Company's anti-microbial coated steel sprinkler pipe, which the Company has not manufactured or sold for several years, is incompatible with chlorinated polyvinyl chloride and caused stress cracking in such pipe manufactured by third parties when installed together in the same sprinkler system, which the Company refers to collectively as the “Special Products Claims.” Tyco International Ltd. (“Tyco”), now Johnson Controls, Inc. (“JCI”), has a contractual obligation to indemnify the Company in respect of all remaining and future claims of incompatibility between the Company's antimicrobial coated steel sprinkler pipe and CPVC pipe used in the same sprinkler system. When Special Products Claims arise, JCI has defended and indemnified the Company as required. As of the date of this filing, no Special Product Claims are currently pending against the Company as JCI has resolved all claims at their sole cost and expense. Accordingly, at this time, the Company does not expect the outcome of the Special Products Claims proceedings, either individually or in the aggregate, to have a material adverse effect on its business, financial condition, results of operations or cash flows, and the Company believes that its reserves are adequate for all remaining contingencies for Special Products Claims and other product liabilities. In addition to the matters discussed above, from time to time, the Company is subject to a number of disputes, administrative proceedings and other claims arising out of the ordinary conduct of the Company ’ s business. These matters generally relate to disputes arising out of the use or installation of the Company ’ s products, product liability litigation, contract disputes, patent infringement accusations, employment matters, personal injury claims and similar matters. On the basis of information currently available to the Company, it does not believe that existing proceedings and claims will have a material adverse effect on its business, financial condition, results of operations or cash flows. However, litigation is unpredictable, and the Company could incur judgments or enter into settlements for current or future claims that could adversely affect its business, financial condition, results of operations or cash flows.

GUARANTEES

GUARANTEES	3 Months Ended
GUARANTEES	Dec. 29, 2023
Guarantees [Abstract]
GUARANTEES	15. GUARANTEES The Company had outstanding letters of credit totaling $2,594 supporting workers ’ compensation and general liability insurance policies as of December 29, 2023. The Company also had surety bonds primarily related to performance guarantees on supply agreements and construction contracts, and payment of duties and taxes totaling $37,722 as of December 29, 2023. In disposing of assets or businesses, the Company often provides representations, warranties and indemnities to cover various risks including unknown damage to the assets, environmental risks involved in the sale of real estate, liability to investigate and remediate environmental contamination at waste disposal sites and manufacturing facilities, and unidentified tax liabilities and legal fees related to periods prior to disposition. The Company does not have the ability to estimate the potential liability from such indemnities because they relate to unknown conditions. However, the Company has no reason to believe that these uncertainties would have a material adverse effect on the Company ’ s business, financial condition, results of operations or cash flows. In the normal course of business, the Company is liable for product performance and contract completion. In the opinion of management, such obligations will not have a material adverse effect on the Company ’ s business, financial condition, results of operations or cash flows.

SEGMENT INFORMATION

SEGMENT INFORMATION	3 Months Ended
SEGMENT INFORMATION	Dec. 29, 2023
Segment Reporting [Abstract]
SEGMENT INFORMATION	16. SEGMENT INFORMATION The Electrical segment manufactures high quality products used in the construction of electrical power systems including conduit, cable and installation accessories. This segment serves contractors in partnership with the electrical wholesale channel. The Safety & Infrastructure segment designs and manufactures solutions including metal framing, mechanical pipe, perimeter security and cable management for the protection and reliability of critical infrastructure. These solutions are marketed to contractors, original equipment manufacturers and end users. Both segments use Adjusted EBITDA as the primary measure of profit and loss. Segment Adjusted EBITDA is income (loss) before income taxes, adjusted to exclude unallocated expenses, depreciation and amortization, interest expense, net, stock-based compensation, loss on extinguishment of debt, certain legal matters, and other items, such as inventory reserves and adjustments, (gain) loss on disposal of property, plant and equipment, insurance recovery related to damages of property, plant and equipment, release of indemnified uncertain tax positions, realized or unrealized gain (loss) on foreign currency impacts of intercompany loans and related forward currency derivatives, gain on purchase of business, loss on assets held for sale, restructuring costs and transaction costs. Intersegment transactions primarily consist of product sales at designated transfer prices on an arm ’ s-length basis. Gross profit earned and reported within the segment is eliminated in the Company ’ s consolidated results. Certain manufacturing and distribution expenses are allocated between the segments on a pro rata basis due to the shared nature of activities. Recorded amounts represent a proportional amount of the quantity of product produced for each segment. Certain assets, such as machinery and equipment and facilities, are not allocated to each segment despite serving both segments. These shared assets are reported within the Safety & Infrastructure segment. The Company allocates certain corporate operating expenses that directly benefit our operating segments, such as insurance and information technology, on a basis that reasonably approximates an estimate of the use of these services. Three months ended December 29, 2023 December 30, 2022 (in thousands) External Net Sales Intersegment Sales Adjusted EBITDA External Net Sales Intersegment Sales Adjusted EBITDA Electrical $ 593,660 $ 1 $ 204,360 $ 638,705 $ — $ 243,836 Safety & Infrastructure 204,821 305 19,512 195,116 143 33,404 Eliminations — (306) — (143) Consolidated operations $ 798,481 $ — $ 833,821 $ — Presented below is a reconciliation of operating Segment Adjusted EBITDA to Income before income taxes: Three months ended (in thousands) December 29, 2023 December 30, 2022 Operating segment Adjusted EBITDA Electrical $ 204,360 $ 243,836 Safety & Infrastructure 19,512 33,404 Total 223,872 277,240 Unallocated expenses (a) (10,349) (13,395) Depreciation and amortization (29,020) (25,967) Interest expense, net (7,793) (9,488) Stock-based compensation (4,757) (5,270) Other (b) (4,300) (1,069) Income before income taxes $ 167,653 $ 222,051 (a) Represents unallocated selling, general and administrative activities and associated expenses including, in part, executive, legal, finance, human resources, information technology, business development and communications. (b) Represents other items, such as inventory reserves and adjustments, loss on disposal of property, plant and equipment, insurance recovery related to damages of property, plant and equipment, release of indemnified uncertain tax positions, gain on purchase of business. realized or unrealized gain (loss) on foreign currency impacts of intercompany loans and related forward currency derivatives, and restructuring charges. The Company ’ s net sales by geography were as follows for the three months ended December 29, 2023 and December 30, 2022: Three months ended (in thousands) December 29, 2023 December 30, 2022 United States $ 708,457 $ 750,087 Other Americas 21,209 20,554 Europe 57,408 52,030 Asia-Pacific 11,407 11,150 Total $ 798,481 $ 833,821 The table below shows the amount of net sales from external customers for each of the Company ’ s product categories which accounted for 10% or more of consolidated net sales in either period for the three months ended December 29, 2023 and December 30, 2022: Three months ended (in thousands) December 29, 2023 December 30, 2022 Metal Electrical Conduit and Fittings $ 139,240 $ 111,158 Electrical Cable & Flexible Conduit 115,693 123,726 Plastic Pipe and Conduit 243,840 316,165 Other Electrical products (a) 94,887 87,656 Electrical 593,660 638,705 Mechanical Pipe 84,498 78,774 Other Safety & Infrastructure products (b) 120,323 116,342 Safety & Infrastructure 204,821 195,116 Net sales $ 798,481 $ 833,821 (a) Other Electrical products includes International Cable Management, Fiberglass Conduit and Corrosion Resistant Conduit (b) Other S&I products includes Metal Framing and Fittings, Construction Services, Perimeter Security and Cable Management

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	3 Months Ended
SUBSEQUENT EVENTS	Dec. 29, 2023
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTS Subsequent to December 29, 2023, the Company has repurchased 148.4 thousand shares at a cost of $22.8 million as of February 1, 2024.

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Dec. 29, 2023	Dec. 30, 2022
Pay vs Performance Disclosure
Net income	$ 138,381	$ 173,492

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Dec. 29, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

BASIS OF PRESENTATION AND SUM_2

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
	Dec. 29, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation — The accompanying unaudited condensed consolidated financial statements of the Company included herein have been prepared in accordance with accounting principles generally accepted in the United States of America ( “ GAAP ” ). These unaudited condensed consolidated financial statements have been prepared in accordance with the Company ’ s accounting policies and on the same basis as those financial statements included in the Company ’ s latest Annual Report on Form 10-K for the year ended September 30, 2023, filed with the U.S. Securities and Exchange Commission (the “ SEC ” ) on November 17, 2023, and should be read in conjunction with those consolidated financial statements and the notes thereto. Certain information and disclosures normally included in the Company ’ s annual financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to the rules and regulations of the SEC. The unaudited condensed consolidated financial statements include the assets and liabilities used in operating the Company ’ s business. All intercompany balances and transactions have been eliminated in consolidation. The results of companies acquired or disposed of are included in the unaudited condensed consolidated financial statements from the effective date of acquisition or up to the date of disposal. These statements include all adjustments (consisting of normal recurring adjustments) that the Company considered necessary to present a fair statement of its results of operations, financial position and cash flows. The results reported in these unaudited condensed consolidated financial statements should not be regarded as necessarily indicative of results that may be expected for the entire year.
Fiscal Periods	Fiscal Periods — The Company has a fiscal year that ends on September 30. The Company ’ s fiscal quarters typically end on the last Friday in December, March and June as it follows a 4-5-4 calendar.
Use of Estimates	Use of Estimates — The preparation of the condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclose contingent assets and liabilities at the date of the condensed consolidated financial statements and report the associated amounts of revenues and expenses. Actual results could differ materially from these estimates.
Recent Accounting Pronouncements	Recent Accounting Pronouncements A summary of recently adopted accounting guidance is as follows. Adoption dates are on the first day of the fiscal year indicated below, unless otherwise specified. ASU Description of ASU Impact to Atkore Adoption Date 2023-07 Segment Reporting (Topic 280); Improvements to Reportable Segment Disclosures The ASU requires companies to provide additional segment disclosures including disclosing title and position of the chief operating decision maker (“CODM”), disclosure of significant segment expenses provided to and reviewed by the CODM, and that public entities provide all annual disclosures about a reportable segment’s profit or loss and assets required by Topic 280 in interim periods. The Company will adopt the standard in the first quarter of fiscal 2025 and include the disclosures required by the ASU within the Segment Footnote. 2025

BASIS OF PRESENTATION AND SUM_3

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)	3 Months Ended
	Dec. 29, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Adopted Accounting Guidance	A summary of recently adopted accounting guidance is as follows. Adoption dates are on the first day of the fiscal year indicated below, unless otherwise specified. ASU Description of ASU Impact to Atkore Adoption Date 2023-07 Segment Reporting (Topic 280); Improvements to Reportable Segment Disclosures The ASU requires companies to provide additional segment disclosures including disclosing title and position of the chief operating decision maker (“CODM”), disclosure of significant segment expenses provided to and reviewed by the CODM, and that public entities provide all annual disclosures about a reportable segment’s profit or loss and assets required by Topic 280 in interim periods. The Company will adopt the standard in the first quarter of fiscal 2025 and include the disclosures required by the ASU within the Segment Footnote. 2025

POSTRETIREMENT BENEFITS (Tables

POSTRETIREMENT BENEFITS (Tables)	3 Months Ended
POSTRETIREMENT BENEFITS (Tables)	Dec. 29, 2023
Retirement Benefits [Abstract]
Schedule of Net Periodic Benefit Cost	The net periodic benefit credit was as follows: Three months ended (in thousands) Note December 29, 2023 December 30, 2022 Interest cost $ 1,316 $ 1,294 Expected return on plan assets (841) (1,257) Amortization of actuarial loss 67 167 Net periodic benefit cost 5 $ 542 $ 204

OTHER EXPENSE, NET (Tables)

OTHER EXPENSE, NET (Tables)	3 Months Ended
OTHER EXPENSE, NET (Tables)	Dec. 29, 2023
Other Income and Expenses [Abstract]
Schedule of Other Expense, Net	Other expense, net consisted of the following: Three months ended (in thousands) December 29, 2023 December 30, 2022 Undesignated foreign currency derivative instruments $ — $ (14) Loss on assets held for sale (64) — Foreign exchange loss on intercompany loans (198) (149) Pension-related benefits 274 204 Other expense, net $ 12 $ 41

EARNINGS PER SHARE (Tables)

EARNINGS PER SHARE (Tables)	3 Months Ended
EARNINGS PER SHARE (Tables)	Dec. 29, 2023
Earnings Per Share [Abstract]
Schedule of Basic and Diluted Net Income Per Share	The following table sets forth the computation of basic and diluted earnings per share: Three months ended (in thousands, except per share data) December 29, 2023 December 30, 2022 Numerator: Net income $ 138,381 $ 173,492 Less: Undistributed earnings allocated to participating securities 2,072 2,807 Net income available to common shareholders $ 136,309 $ 170,685 Denominator: Basic weighted average common shares outstanding 37,242 40,085 Effect of dilutive securities: Non-participating employee stock options (1) 503 528 Diluted weighted average common shares outstanding 37,745 40,613 Basic earnings per share $ 3.66 $ 4.26 Diluted earnings per share $ 3.61 $ 4.20 (1) Stock options to purchase shares of common stock that would have been anti-dilutive are not included in the calculation. There were no anti-dilutive options outstanding during the three months ended December 29, 2023 and December 30, 2022.

ACCUMULATED OTHER COMPREHENSI_2

ACCUMULATED OTHER COMPREHENSIVE LOSS (Tables)	3 Months Ended
ACCUMULATED OTHER COMPREHENSIVE LOSS (Tables)	Dec. 29, 2023
Equity [Abstract]
Schedule of Accumulated Other Comprehensive Loss	The following table presents the changes in accumulated other comprehensive loss by component for the three months ended December 29, 2023 and December 30, 2022. (in thousands) Defined Benefit Currency Total Balance as of September 30, 2023 $ (10,801) $ (23,139) $ (33,940) Other comprehensive income before reclassifications — 9,727 9,727 Amounts reclassified from accumulated other 53 — 53 Net current period other comprehensive income 53 9,727 9,780 Balance as of December 29, 2023 $ (10,748) $ (13,412) $ (24,160) (in thousands) Defined Benefit Currency Total Balance as of September 30, 2022 $ (16,795) $ (33,351) $ (50,146) Other comprehensive income before reclassifications — 11,262 11,262 Amounts reclassified from accumulated other 62 — 62 Net current period other comprehensive income 62 11,262 11,324 Balance as of December 30, 2022 $ (16,733) $ (22,089) $ (38,822)

INVENTORIES, NET (Tables)

INVENTORIES, NET (Tables)	3 Months Ended
INVENTORIES, NET (Tables)	Dec. 29, 2023
Inventory Disclosure [Abstract]
Schedule of Inventory, Current	(in thousands) December 29, 2023 September 30, 2023 Purchased materials and manufactured parts, net $ 194,417 $ 231,518 Work in process, net 61,993 60,524 Finished goods, net 237,227 201,810 Inventories, net $ 493,637 $ 493,852

PROPERTY, PLANT AND EQUIPMENT (

PROPERTY, PLANT AND EQUIPMENT (Tables)	3 Months Ended
PROPERTY, PLANT AND EQUIPMENT (Tables)	Dec. 29, 2023
Property, Plant and Equipment [Abstract]
Schedule of Property, Plant and Equipment	As of December 29, 2023, and September 30, 2023, property, plant and equipment and accumulated depreciation were as follows: (in thousands) December 29, 2023 September 30, 2023 Land $ 29,357 $ 29,082 Buildings and related improvements 184,606 182,760 Machinery and equipment 524,607 513,563 Leasehold improvements 16,901 15,910 Software 46,807 47,072 Construction in progress 235,549 206,311 Property, plant and equipment, at cost 1,037,827 994,698 Accumulated depreciation (450,844) (435,657) Property, plant and equipment, net $ 586,983 $ 559,041

GOODWILL AND INTANGIBLE ASSETS

GOODWILL AND INTANGIBLE ASSETS (Tables)	3 Months Ended
GOODWILL AND INTANGIBLE ASSETS (Tables)	Dec. 29, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	Changes in the carrying amount of goodwill are as follows: (in thousands) Electrical Safety & Infrastructure Total Balance as of September 30, 2023 $ 258,427 $ 52,679 $ 311,106 Exchange rate effects 1,667 187 1,854 Balance as of December 29, 2023 $ 260,094 $ 52,866 $ 312,960
Schedule of Finite-Lived Intangible Assets	The following table provides the gross carrying value, accumulated amortization and net carrying value for each major class of intangible asset: December 29, 2023 September 30, 2023 (in thousands) Weighted Average Useful Life (Years) Gross Carrying Value Accumulated Amortization Net Carrying Value Gross Carrying Value Accumulated Amortization Net Carrying Value Amortizable intangible assets: Customer relationships 11 $ 596,522 $ (330,703) $ 265,819 $ 596,396 $ (318,058) $ 278,338 Other 8 46,259 (23,684) 22,575 43,633 (20,406) 23,227 Total 642,781 (354,387) 288,394 640,029 (338,464) 301,565 Indefinite-lived intangible assets: Trade names 92,811 — 92,811 92,806 — 92,806 Total $ 735,592 $ (354,387) $ 381,205 $ 732,835 $ (338,464) $ 394,372
Schedule of Indefinite-Lived Intangible Assets	The following table provides the gross carrying value, accumulated amortization and net carrying value for each major class of intangible asset: December 29, 2023 September 30, 2023 (in thousands) Weighted Average Useful Life (Years) Gross Carrying Value Accumulated Amortization Net Carrying Value Gross Carrying Value Accumulated Amortization Net Carrying Value Amortizable intangible assets: Customer relationships 11 $ 596,522 $ (330,703) $ 265,819 $ 596,396 $ (318,058) $ 278,338 Other 8 46,259 (23,684) 22,575 43,633 (20,406) 23,227 Total 642,781 (354,387) 288,394 640,029 (338,464) 301,565 Indefinite-lived intangible assets: Trade names 92,811 — 92,811 92,806 — 92,806 Total $ 735,592 $ (354,387) $ 381,205 $ 732,835 $ (338,464) $ 394,372
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	Expected amortization expense for intangible assets for the remainder of fiscal 2024 and over the next five years and thereafter is as follows: (in thousands) Remaining 2024 $ 41,242 2025 43,326 2026 40,726 2027 39,610 2028 29,445 2029 28,293 Thereafter 65,752

DEBT (Tables)

DEBT (Tables)	3 Months Ended
DEBT (Tables)	Dec. 29, 2023
Debt Disclosure [Abstract]
Schedule of Debt	Debt as of December 29, 2023 and September 30, 2023 was as follows: (in thousands) December 29, 2023 September 30, 2023 Senior Secured Term Loan Facility due May 26, 2028 $ 371,738 $ 371,667 Senior Notes due June 2031 400,000 400,000 Deferred financing costs (8,513) (8,980) Long-term debt $ 763,225 $ 762,687

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	3 Months Ended
FAIR VALUE MEASUREMENTS (Tables)	Dec. 29, 2023
Fair Value Disclosures [Abstract]
Schedule of Assets and Liabilities Measured at Fair Value	The following table presents the Company ’ s assets and liabilities measured at fair value: December 29, 2023 September 30, 2023 (in thousands) Level 1 Level 2 Level 1 Level 2 Assets Cash equivalents $ 298,683 $ — $ 321,282 $ —
Schedule of Estimated Fair Value of Financial Instruments Not Carried at Fair Value	The estimated fair value of financial instruments not carried at fair value in the condensed consolidated balance sheets were as follows: December 29, 2023 September 30, 2023 (in thousands) Carrying Value Fair Value Carrying Value Fair Value Senior Secured Term Loan Facility due May 26, 2028 $ 373,000 $ 373,116 $ 373,000 $ 372,068 Senior Notes due June 2031 400,000 360,272 400,000 334,368 Total Debt $ 773,000 $ 733,388 $ 773,000 $ 706,436

SEGMENT INFORMATION (Tables)

SEGMENT INFORMATION (Tables)	3 Months Ended
SEGMENT INFORMATION (Tables)	Dec. 29, 2023
Segment Reporting [Abstract]
Schedule of Segment Information	Three months ended December 29, 2023 December 30, 2022 (in thousands) External Net Sales Intersegment Sales Adjusted EBITDA External Net Sales Intersegment Sales Adjusted EBITDA Electrical $ 593,660 $ 1 $ 204,360 $ 638,705 $ — $ 243,836 Safety & Infrastructure 204,821 305 19,512 195,116 143 33,404 Eliminations — (306) — (143) Consolidated operations $ 798,481 $ — $ 833,821 $ — Presented below is a reconciliation of operating Segment Adjusted EBITDA to Income before income taxes: Three months ended (in thousands) December 29, 2023 December 30, 2022 Operating segment Adjusted EBITDA Electrical $ 204,360 $ 243,836 Safety & Infrastructure 19,512 33,404 Total 223,872 277,240 Unallocated expenses (a) (10,349) (13,395) Depreciation and amortization (29,020) (25,967) Interest expense, net (7,793) (9,488) Stock-based compensation (4,757) (5,270) Other (b) (4,300) (1,069) Income before income taxes $ 167,653 $ 222,051 (a) Represents unallocated selling, general and administrative activities and associated expenses including, in part, executive, legal, finance, human resources, information technology, business development and communications. (b) Represents other items, such as inventory reserves and adjustments, loss on disposal of property, plant and equipment, insurance recovery related to damages of property, plant and equipment, release of indemnified uncertain tax positions, gain on purchase of business. realized or unrealized gain (loss) on foreign currency impacts of intercompany loans and related forward currency derivatives, and restructuring charges. The Company ’ s net sales by geography were as follows for the three months ended December 29, 2023 and December 30, 2022: Three months ended (in thousands) December 29, 2023 December 30, 2022 United States $ 708,457 $ 750,087 Other Americas 21,209 20,554 Europe 57,408 52,030 Asia-Pacific 11,407 11,150 Total $ 798,481 $ 833,821 The table below shows the amount of net sales from external customers for each of the Company ’ s product categories which accounted for 10% or more of consolidated net sales in either period for the three months ended December 29, 2023 and December 30, 2022: Three months ended (in thousands) December 29, 2023 December 30, 2022 Metal Electrical Conduit and Fittings $ 139,240 $ 111,158 Electrical Cable & Flexible Conduit 115,693 123,726 Plastic Pipe and Conduit 243,840 316,165 Other Electrical products (a) 94,887 87,656 Electrical 593,660 638,705 Mechanical Pipe 84,498 78,774 Other Safety & Infrastructure products (b) 120,323 116,342 Safety & Infrastructure 204,821 195,116 Net sales $ 798,481 $ 833,821 (a) Other Electrical products includes International Cable Management, Fiberglass Conduit and Corrosion Resistant Conduit (b) Other S&I products includes Metal Framing and Fittings, Construction Services, Perimeter Security and Cable Management

REVENUE FROM CONTRACTS WITH C_2

REVENUE FROM CONTRACTS WITH CUSTOMERS (Details) $ in Thousands	3 Months Ended
	Dec. 29, 2023 USD ($) performance_obligation
Disaggregation of Revenue [Line Items]
Number of performance obligations \| performance_obligation	2
Reduction of revenue for economic value of tax credits to be transferred	$ 14,853
Benefit to tax provision related to tax credits	19,127,000
Liability for credits to be transferred	29,310
Solar tax credit receivable	$ 64,595,000
Minimum
Disaggregation of Revenue [Line Items]
Period of payment received from related performance obligation satisfied	30 days
Maximum
Disaggregation of Revenue [Line Items]
Period of payment received from related performance obligation satisfied	60 days
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-12-30
Disaggregation of Revenue [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year

ACQUISITIONS - Narrative (Detai

ACQUISITIONS - Narrative (Details) - USD ($) $ in Thousands		3 Months Ended	11 Months Ended	12 Months Ended
ACQUISITIONS - Narrative (Details) - USD ($) $ in Thousands	Nov. 07, 2022	Dec. 29, 2023	Sep. 30, 2023	Sep. 30, 2023
Business Acquisition [Line Items]
Goodwill		$ 312,960	$ 311,106	$ 311,106
Cascade and Northwest Polymers
Business Acquisition [Line Items]
Payments to acquire business		$ 5,973
Elite Polymer Solutions
Business Acquisition [Line Items]
Payments to acquire business	$ 75,981
Purchase price of business acquisition	90,230
Purchase price payable	14,000
Purchase price paid subsequent to acquisition			$ 500
Goodwill	18,669
Identifiable intangible assets acquired	68,480
Working capital and other net tangible assets acquired	3,082
Elite Polymer Solutions \| Customer relationships
Business Acquisition [Line Items]
Identifiable intangible assets acquired	$ 68,200
Weighted average useful life (years)	8 years
Elite Polymer Solutions \| Selling, General and Administrative Expenses
Business Acquisition [Line Items]
Business acquisition-related expenses				$ 968

POSTRETIREMENT BENEFITS - Net P

POSTRETIREMENT BENEFITS - Net Periodic Benefit Cost (Details) - Pension Plan - USD ($) $ in Thousands	3 Months Ended
	Dec. 29, 2023	Dec. 30, 2022
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 1,316	$ 1,294
Expected return on plan assets	(841)	(1,257)
Amortization of actuarial loss	67	167
Net periodic benefit cost	$ 542	$ 204

OTHER EXPENSE, NET (Details)

OTHER EXPENSE, NET (Details) - USD ($) $ in Thousands	3 Months Ended
OTHER EXPENSE, NET (Details) - USD ($) $ in Thousands	Dec. 29, 2023	Dec. 30, 2022
Other Income and Expenses [Abstract]
Undesignated foreign currency derivative instruments	$ 0	$ (14)
Loss on assets held for sale	(64)	0
Foreign exchange loss on intercompany loans	(198)	(149)
Pension-related benefits	274	204
Other expense, net	$ 12	$ 41

INCOME TAXES (Details)

INCOME TAXES (Details) - USD ($) $ in Thousands	3 Months Ended
INCOME TAXES (Details) - USD ($) $ in Thousands	Dec. 29, 2023	Dec. 30, 2022
Income Tax Disclosure [Abstract]
Effective income tax rate	17.50%	21.90%
Income tax expense	$ 29,272	$ 48,559
Benefit to tax provision related to tax credits	$ 19,127,000

EARNINGS PER SHARE (Details)

EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Dec. 29, 2023	Dec. 30, 2022
Numerator:
Net income	$ 138,381	$ 173,492
Less: Undistributed earnings allocated to participating securities	2,072	2,807
Net income available to common shareholders	136,309	170,685
Net income available to common shareholders	$ 136,309	$ 170,685
Denominator:
Basic weighted average common shares outstanding (in shares)	37,242	40,085
Effect of dilutive securities: Non-participating employee stock options (in shares)	503	528
Diluted weighted average common shares outstanding (in shares)	37,745	40,613
Basic earnings per share (in dollars per share)	$ 3.66	$ 4.26
Diluted earnings per share (in dollars per share)	$ 3.61	$ 4.20
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	0	0

ACCUMULATED OTHER COMPREHENSI_3

ACCUMULATED OTHER COMPREHENSIVE LOSS (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 29, 2023	Dec. 30, 2022
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	$ 1,468,119	$ 1,249,787
Other comprehensive income before reclassifications	9,727	11,262
Amounts reclassified from accumulated other comprehensive income, net of tax	53	62
Total other comprehensive income	9,780	11,324
Balance at end of period	1,502,345	1,275,042
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	(33,940)	(50,146)
Total other comprehensive income	9,780	11,324
Balance at end of period	(24,160)	(38,822)
Defined Benefit Pension Items
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	(10,801)	(16,795)
Other comprehensive income before reclassifications	0	0
Amounts reclassified from accumulated other comprehensive income, net of tax	53	62
Total other comprehensive income	53	62
Balance at end of period	(10,748)	(16,733)
Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	(23,139)	(33,351)
Other comprehensive income before reclassifications	9,727	11,262
Amounts reclassified from accumulated other comprehensive income, net of tax	0	0
Total other comprehensive income	9,727	11,262
Balance at end of period	$ (13,412)	$ (22,089)

INVENTORIES, NET - Narrative (D

INVENTORIES, NET - Narrative (Details) - USD ($) $ in Thousands	Dec. 29, 2023	Sep. 30, 2023	Dec. 30, 2022
Inventory Disclosure [Abstract]
Inventories at lower of LIFO cost or market	86%		82%
FIFO inventory, higher (lower) than reported	$ 4,574	$ 29,826
Excess and obsolete inventory reserve	$ 26,330	$ 25,585

INVENTORIES, NET - Schedule of

INVENTORIES, NET - Schedule of Company Inventories (Details) - USD ($) $ in Thousands	Dec. 29, 2023	Sep. 30, 2023
Inventory Disclosure [Abstract]
Purchased materials and manufactured parts, net	$ 194,417	$ 231,518
Work in process, net	61,993	60,524
Finished goods, net	237,227	201,810
Inventories, net	$ 493,637	$ 493,852

PROPERTY, PLANT AND EQUIPMENT_2

PROPERTY, PLANT AND EQUIPMENT (Details) - USD ($) $ in Thousands	Dec. 29, 2023	Sep. 30, 2023
Property, Plant and Equipment [Line Items]
Property, plant and equipment, at cost	$ 1,037,827	$ 994,698
Accumulated depreciation	(450,844)	(435,657)
Property, plant and equipment, net	586,983	559,041
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, at cost	29,357	29,082
Buildings and related improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, at cost	184,606	182,760
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, at cost	524,607	513,563
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, at cost	16,901	15,910
Software
Property, Plant and Equipment [Line Items]
Property, plant and equipment, at cost	46,807	47,072
Construction in progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, at cost	$ 235,549	$ 206,311

PROPERTY, PLANT AND EQUIPMENT -

PROPERTY, PLANT AND EQUIPMENT - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 29, 2023	Dec. 30, 2022
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 14,553	$ 13,171

GOODWILL AND INTANGIBLE ASSET_2

GOODWILL AND INTANGIBLE ASSETS - Goodwill (Details) $ in Thousands	3 Months Ended
	Dec. 29, 2023 USD ($)
Goodwill [Roll Forward]
Balance at beginning of period	$ 311,106
Exchange rate effects	1,854
Balance at end of period	312,960
Electrical
Goodwill [Roll Forward]
Balance at beginning of period	258,427
Exchange rate effects	1,667
Balance at end of period	260,094
Safety & Infrastructure
Goodwill [Roll Forward]
Balance at beginning of period	52,679
Exchange rate effects	187
Balance at end of period	$ 52,866

GOODWILL AND INTANGIBLE ASSET_3

GOODWILL AND INTANGIBLE ASSETS - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 29, 2023	Dec. 30, 2022
Goodwill [Line Items]
Intangible asset amortization	$ 14,467	$ 12,796
Electrical
Goodwill [Line Items]
Accumulated impairment loss	5,645
Safety & Infrastructure
Goodwill [Line Items]
Accumulated impairment loss	$ 43,000

GOODWILL AND INTANGIBLE ASSET_4

GOODWILL AND INTANGIBLE ASSETS - Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 29, 2023	Sep. 30, 2023
Amortizable intangible assets:
Gross Carrying Value	$ 642,781	$ 640,029
Accumulated Amortization	(354,387)	(338,464)
Net Carrying Value	288,394	301,565
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Gross Carrying Value	735,592	732,835
Net Carrying Value	381,205	394,372
Trade names
Indefinite-lived Intangible Assets [Line Items]
Trade names	92,811	92,806
Customer relationships
Amortizable intangible assets:
Gross Carrying Value	596,522	596,396
Accumulated Amortization	(330,703)	(318,058)
Net Carrying Value	$ 265,819	278,338
Customer relationships \| Weighted Average Useful Life (Years)
Amortizable intangible assets:
Weighted Average Useful Life (Years)	11 years
Other
Amortizable intangible assets:
Gross Carrying Value	$ 46,259	43,633
Accumulated Amortization	(23,684)	(20,406)
Net Carrying Value	$ 22,575	$ 23,227
Other \| Weighted Average Useful Life (Years)
Amortizable intangible assets:
Weighted Average Useful Life (Years)	8 years

GOODWILL AND INTANGIBLE ASSET_5

GOODWILL AND INTANGIBLE ASSETS - Expected Amortization Expense (Details) $ in Thousands	Dec. 29, 2023 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Remaining 2024	$ 41,242
2025	43,326
2026	40,726
2027	39,610
2028	29,445
2029	28,293
Thereafter	$ 65,752

DEBT - Schedule of Debt (Detail

DEBT - Schedule of Debt (Details) - USD ($) $ in Thousands	Dec. 29, 2023	Sep. 30, 2023
Debt Instrument [Line Items]
Deferred financing costs	$ (8,513)	$ (8,980)
Long-term debt	763,225	762,687
Secured Debt \| Senior Secured Term Loan Facility due May 26, 2028
Debt Instrument [Line Items]
Long-term debt, gross	371,738	371,667
Secured Debt \| Senior Notes due June 2031
Debt Instrument [Line Items]
Long-term debt, gross	$ 400,000	$ 400,000

DEBT - Narrative (Details)

DEBT - Narrative (Details) - USD ($)	Mar. 15, 2023	May 26, 2021	Dec. 29, 2023	Sep. 30, 2023
New Senior Secured Term Loan Facility \| Secured Overnight Financing Rate (SOFR) \| Secured Debt
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2%
New Senior Secured Term Loan Facility \| Secured Overnight Financing Rate (SOFR) \| Secured Debt \| One-month interest period
Debt Instrument [Line Items]
Credit spread adjustment	0.11448%
New Senior Secured Term Loan Facility \| Secured Overnight Financing Rate (SOFR) \| Secured Debt \| Three-month interest period
Debt Instrument [Line Items]
Credit spread adjustment	0.26161%
New Senior Secured Term Loan Facility \| Secured Overnight Financing Rate (SOFR) \| Secured Debt \| Six-month interest period
Debt Instrument [Line Items]
Credit spread adjustment	0.42826%
Senior Notes due June 2031 \| Senior Notes
Debt Instrument [Line Items]
Debt face amount		$ 400,000,000
Debt instrument, interest rate, stated percentage		4.25%
Line of credit \| ABL Credit Facility \| Atkore International
Debt Instrument [Line Items]
Credit facility, aggregate commitments			$ 325,000,000
Credit facility available borrowing capacity			$ 322,406,000	$ 322,406,000
Line of credit \| Amended ABL Credit Facility \| Secured Debt
Debt Instrument [Line Items]
Debt instrument, extended term, period from amendment date		5 years
Debt instrument, extended term, period prior to maturity date		91 days
Line of credit facility, term, outstanding obligations threshold amount		$ 100,000,000
Line of credit \| Amended ABL Credit Facility \| Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Credit spread adjustment		0.10%
Line of credit \| Amended ABL Credit Facility \| Secured Overnight Financing Rate (SOFR) \| Minimum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		1.25%
Line of credit \| Amended ABL Credit Facility \| Secured Overnight Financing Rate (SOFR) \| Maximum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		1.75%

FAIR VALUE MEASUREMENTS - Asset

FAIR VALUE MEASUREMENTS - Assets and Liabilities Measured at Fair Value (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Dec. 29, 2023	Sep. 30, 2023
Level 1
Assets
Cash equivalents	$ 298,683	$ 321,282
Level 2
Assets
Cash equivalents	$ 0	$ 0

FAIR VALUE MEASUREMENTS - Estim

FAIR VALUE MEASUREMENTS - Estimated Fair Value of Financial Instruments Not Carried at Fair Value (Details) - Secured Debt - USD ($) $ in Thousands	Dec. 29, 2023	Sep. 30, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying Value	$ 773,000	$ 773,000
Fair Value	733,388	706,436
Senior Secured Term Loan Facility due May 26, 2028
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying Value	373,000	373,000
Fair Value	373,116	372,068
Senior Notes due June 2031
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying Value	400,000	400,000
Fair Value	$ 360,272	$ 334,368

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands	Dec. 29, 2023 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Purchase obligation for the rest of fiscal year 2023	$ 281,447
Purchase obligation for fiscal year 2024	$ 13,895

GUARANTEES (Details)

GUARANTEES (Details) $ in Thousands	Dec. 29, 2023 USD ($)
Performance Guarantee, Workers' Compensation and General Liability Policies
Guarantor Obligations [Line Items]
Guarantees	$ 2,594
Surety bond
Guarantor Obligations [Line Items]
Guarantees	$ 37,722

SEGMENT INFORMATION -Schedule o

SEGMENT INFORMATION -Schedule of Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 29, 2023	Dec. 30, 2022
Segment Reporting Information [Line Items]
Net sales	$ 798,481	$ 833,821
Electrical
Segment Reporting Information [Line Items]
Net sales	593,660	638,705
Safety & Infrastructure
Segment Reporting Information [Line Items]
Net sales	204,821	195,116
Operating Segments
Segment Reporting Information [Line Items]
Net sales	798,481	833,821
Adjusted EBITDA	223,872	277,240
Operating Segments \| Electrical
Segment Reporting Information [Line Items]
Net sales	593,660	638,705
Adjusted EBITDA	204,360	243,836
Operating Segments \| Safety & Infrastructure
Segment Reporting Information [Line Items]
Net sales	204,821	195,116
Adjusted EBITDA	19,512	33,404
Intersegment Sales
Segment Reporting Information [Line Items]
Net sales	(306)	(143)
Intersegment Sales \| Electrical
Segment Reporting Information [Line Items]
Net sales	1	0
Intersegment Sales \| Safety & Infrastructure
Segment Reporting Information [Line Items]
Net sales	$ 305	$ 143

SEGMENT INFORMATION - Reconcili

SEGMENT INFORMATION - Reconciliation of Operating Segment Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 29, 2023	Dec. 30, 2022
Segment Reporting Information [Line Items]
Unallocated expenses	$ (10,349)	$ (13,395)
Depreciation and amortization	(29,020)	(25,967)
Interest expense, net	(7,793)	(9,488)
Stock-based compensation	(4,757)	(5,270)
Other	(4,300)	(1,069)
Income before income taxes	167,653	222,051
Operating Segments
Segment Reporting Information [Line Items]
Adjusted EBITDA	223,872	277,240
Operating Segments \| Electrical
Segment Reporting Information [Line Items]
Adjusted EBITDA	204,360	243,836
Operating Segments \| Safety & Infrastructure
Segment Reporting Information [Line Items]
Adjusted EBITDA	$ 19,512	$ 33,404

SEGMENT INFORMATION - Schedule

SEGMENT INFORMATION - Schedule of Long-lived Assets and Net Sales By Geography (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 29, 2023	Dec. 30, 2022
Disaggregation of Revenue [Line Items]
Net sales	$ 798,481	$ 833,821
United States
Disaggregation of Revenue [Line Items]
Net sales	708,457	750,087
Other Americas
Disaggregation of Revenue [Line Items]
Net sales	21,209	20,554
Europe
Disaggregation of Revenue [Line Items]
Net sales	57,408	52,030
Asia-Pacific
Disaggregation of Revenue [Line Items]
Net sales	$ 11,407	$ 11,150

SEGMENT INFORMATION - Schedul_2

SEGMENT INFORMATION - Schedule of Net Sales From External Customers by Product Category (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 29, 2023	Dec. 30, 2022
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	$ 798,481	$ 833,821
Electrical
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	593,660	638,705
Electrical \| Metal Electrical Conduit and Fittings
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	139,240	111,158
Electrical \| Electrical Cable & Flexible Conduit
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	115,693	123,726
Electrical \| Plastic Pipe and Conduit
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	243,840	316,165
Electrical \| Other Electrical products (a)
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	94,887	87,656
Safety & Infrastructure
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	204,821	195,116
Safety & Infrastructure \| Mechanical Pipe
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	84,498	78,774
Safety & Infrastructure \| Other Safety & Infrastructure products (b)
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	$ 120,323	$ 116,342

SUBSEQUENT EVENTS (Details)

SUBSEQUENT EVENTS (Details) - Subsequent Event - USD ($) $ / shares in Units, $ in Millions		1 Months Ended
	Jan. 30, 2024	Feb. 01, 2024
Subsequent Event [Line Items]
Stock repurchased (in shares)		148,400
Stock repurchased value		$ 22.8
Dividends declared (in dollars per share)	$ 0.32