XML 96 R85.htm IDEA: XBRL DOCUMENT v3.21.1
Credit Enhancement Receivable, Credit Enhancement Deposit and Contingent Liability - Narrative (Details) - USD ($)
3 Months Ended
Mar. 23, 2021
Mar. 31, 2021
Mar. 31, 2020
Dec. 31, 2020
Credit Enhancement Receivable Contingent Liability And Credit Enhancement Deposit        
Credit enhancement receivable   $ 0   $ 0
Deposit in Fannie Mae restricted liquidity account   25,000,000.0   25,000,000.0
Returned the credit enhancement deposit $ 25,000,000      
DB Cayman | Credit Risk        
Credit Enhancement Receivable Contingent Liability And Credit Enhancement Deposit        
Reimbursements under serving agreement   $ 0 $ 0  
Percentage of contingent payment (in percentage)   50.00%    
Contingent liability       $ 12,300,000