Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies - Additional Information (Detail)

v3.22.0.1
Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands
 3 Months Ended 9 Months Ended 12 Months Ended
Dec. 12, 2020
Mar. 31, 2021
Dec. 31, 2021
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Initial Public Offering            
Reverse mortgage loans held for sale       $ 5,165,479 $ 4,457,805  
Percentage of maximum claim amount       98.00%    
Advertising expense   $ 10,600 $ 30,800   37,500 $ 27,200
Percentage of receivables due from Investors     100.00% 100.00%    
Non-agency reverse            
Initial Public Offering            
Reverse mortgage loans held for sale       $ 4,285,661 $ 3,777,346  
Before October Two Twenty Seventeen            
Initial Public Offering            
Rate of MIP amount on mortgage balance for loans     0.50% 0.50%    
After October Two Twenty Seventeen            
Initial Public Offering            
Rate of MIP amount on mortgage balance for loans     1.25% 1.25%    
Minimum            
Initial Public Offering            
Threshold for reporting the disposition of a business on form eight K increase to conform to requirements for reporting business acquisitions, percentage       10.00%    
Maintenance fee rate       0.05%    
Eligible incentive compensation rate       5.00%    
Minimum | Non-agency reverse            
Initial Public Offering            
Reverse mortgage loans held for sale       $ 400    
Maximum            
Initial Public Offering            
Threshold for reporting the disposition of a business on form eight K increase to conform to requirements for reporting business acquisitions, percentage       20.00%    
Maintenance fee rate       0.25%    
Eligible incentive compensation rate       15.00%    
Maximum | Non-agency reverse            
Initial Public Offering            
Reverse mortgage loans held for sale       $ 4,000    
Earnout shares tranche one            
Initial Public Offering            
Volume weighted average price of shares       $ 12.50    
Number of trading days for determining the volume weighted average share price       20 days    
Number of consecutive trading days for determining the volume weighted average share price       30 days    
Percentage of the earnout shares to be issued     50.00% 50.00%    
Earnout shares tranche two            
Initial Public Offering            
Volume weighted average price of shares       $ 15.00    
Number of trading days for determining the volume weighted average share price       20 days    
Number of consecutive trading days for determining the volume weighted average share price       30 days    
Percentage of the earnout shares to be issued     50.00% 50.00%    
Tax receivable agreement obligation            
Initial Public Offering            
Percentage of realized tax benefits payable pursuant to an agreement       85.00%    
Tax receivable agreement obligation | FoA Equity            
Initial Public Offering            
Tax Liability Pursuant To An Agreement     $ 34,600 $ 34,600    
Class B Units [Member] | Buy to Rent Platform Holdings L P [Member] | Finance of America Holdings LLC [Member]            
Initial Public Offering            
Stock redeemed or called during period value $ 203,200