| Cover | Dec. 22, 2022 |
| Document Information [Line Items] | |
| Document Type | 8-K |
| Document Period End Date | Dec. 22, 2022 |
| Entity Registrant Name | OPAL Fuels Inc. |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-40272 |
| Entity Tax Identification Number | 98-1578357 |
| Entity Address, Address Line One | One North Lexington Avenue |
| Entity Address, Address Line Two | Suite 1450 |
| 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 | 705-4000 |
| Written Communications | true |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | true |
| Entity Ex Transition Period | false |
| Entity Central Index Key | 0001842279 |
| Amendment Flag | false |
| Common Class A | |
| Document Information [Line Items] | |
| Title of 12(b) Security | Class A Common Stock, par value $.0001 per share |
| Trading Symbol | OPAL |
| Security Exchange Name | NASDAQ |
| Warrant | |
| Document Information [Line Items] | |
| Title of 12(b) Security | Warrants, each whole warrant exercisable for one share of Class A Common Stock |
| Trading Symbol | OPALW |
| Security Exchange Name | NASDAQ |
