| Document and Entity Information | Dec. 09, 2021 |
| Document And Entity Information [Line Items] | |
| Amendment Flag | true |
| Entity Central Index Key | 0001828723 |
| Document Type | 8-K/A |
| Document Period End Date | Dec. 9, 2021 |
| Entity Registrant Name | Altus Power, Inc. |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 001-39798 |
| Entity Tax Identification Number | 85-3448396 |
| Entity Address, Address Line One | 2200 Atlantic Street |
| Entity Address, Address Line Two | 6th Floor |
| Entity Address, City or Town | Stamford |
| Entity Address, State or Province | CT |
| Entity Address, Postal Zip Code | 06902 |
| City Area Code | (203) |
| Local Phone Number | 698-0090 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | true |
| Entity Ex Transition Period | false |
| Amendment Description | This Amendment No. 1 on Form 8-K/A (“Amendment No. 1”) amends the Current Report on Form 8-K of Altus Power, Inc., a Delaware corporation (the “Company”), filed on December 13, 2021 (the “Original Report”), in which the Company reports, among other events, the completion of the Business Combination (as defined in the Original Report). This Amendment No. 1 is being filed in order to disclose information required by Items 1.01, 2.03, 5.05 and 8.01 of Form 8-K. This Amendment No. 1 does not amend any other item of the Original Report or purport to provide an update or a discussion of any developments at the Company or its subsidiaries subsequent to the filing date of the Original Report, except as indicated below under 1.01, 2.03, 5.05 and 8.01. The information previously reported in or filed with the Original Report is hereby incorporated by reference to this Amendment No. 1. |
| Class 160 A Common Stock Par Value 0.0001 Per Share [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Class A common stock, par value $0.0001 per share |
| Trading Symbol | AMPS |
| Security Exchange Name | NYSE |
| Warrant [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Warrants to purchase one share of common stock, each at an exercise price of $11.00 |
| Trading Symbol | AMPS WS |
| Security Exchange Name | NYSE |
