| Cover | Sep. 20, 2022 |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Sep. 20, 2022 |
| Entity File Number | 001-39523 |
| Entity Registrant Name | North Mountain Merger Corp. |
| Entity Central Index Key | 0001819157 |
| Entity Tax Identification Number | 85-1960216 |
| Entity Incorporation, State or Country Code | DE |
| Entity Address, Address Line One | 767 Fifth Avenue |
| Entity Address, Address Line Two | 9th Floor |
| Entity Address, City or Town | New York |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 10153 |
| City Area Code | 646 |
| Local Phone Number | 446-2700 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | true |
| Elected Not To Use the Extended Transition Period | false |
| Units, each consisting of one share of Class A common stock, $0.0001 par value, and one-half of one redeemable warrant | |
| Title of 12(b) Security | Units, each consisting of one share of Class A common stock, $0.0001 par value, and one-half of one redeemable warrant |
| Trading Symbol | NMMCU |
| Security Exchange Name | NASDAQ |
| Shares of Class A common stock | |
| Title of 12(b) Security | Shares of Class A common stock |
| Trading Symbol | NMMC |
| Security Exchange Name | NASDAQ |
| Redeemable warrants included as part of the units | |
| Title of 12(b) Security | Redeemable warrants included as part of the units |
| Trading Symbol | NMMCW |
| Security Exchange Name | NASDAQ |
