| Document and Entity Information | Mar. 02, 2022 |
| Document And Entity Information [Line Items] | |
| Amendment Flag | false |
| Entity Central Index Key | 0001828937 |
| Document Type | 8-K |
| Document Period End Date | Mar. 2, 2022 |
| Entity Registrant Name | FINANCE OF AMERICA COMPANIES INC. |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 001-40308 |
| Entity Tax Identification Number | 85-3474065 |
| Entity Address, Address Line One | 909 Lake Carolyn Parkway |
| Entity Address, Address Line Two | Suite 1550 |
| Entity Address, City or Town | Irving |
| Entity Address, State or Province | TX |
| Entity Address, Postal Zip Code | 75039 |
| City Area Code | (877) |
| Local Phone Number | 202-2666 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Common Stock [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Class A Common Stock, par value $0.0001 per share |
| Trading Symbol | FOA |
| Security Exchange Name | NYSE |
| Warrant [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Warrants to purchase shares of Class A Common Stock |
| Trading Symbol | FOA.WS |
| Security Exchange Name | NYSE |
