| Document and Entity Information | Oct. 28, 2022 |
| Entity Listings [Line Items] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Oct. 28, 2022 |
| Entity File Number | 001-39939 |
| Entity Registrant Name | FORTISTAR SUSTAINABLE SOLUTIONS CORP. |
| Entity Central Index Key | 0001822862 |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 85-2693583 |
| Entity Address, Address Line One | One North Lexington Avenue |
| Entity Address, City or Town | White Plains |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 10601 |
| City Area Code | 914 |
| Local Phone Number | 421-4900 |
| Entity Emerging Growth Company | true |
| Entity Ex Transition Period | false |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Common Stock [Member] | |
| Entity Listings [Line Items] | |
| Title of 12(b) Security | Units |
| Trading Symbol | FSSIU |
| Security Exchange Name | NASDAQ |
| Class A Common Stock [Member] | |
| Entity Listings [Line Items] | |
| Title of 12(b) Security | Class A Common Stock |
| Trading Symbol | FSSI |
| Security Exchange Name | NASDAQ |
| Warrants [Member] | |
| Entity Listings [Line Items] | |
| Title of 12(b) Security | Warrants |
| Trading Symbol | FSSIW |
| Security Exchange Name | NASDAQ |
