Quarterly report pursuant to Section 13 or 15(d)

Business, Basis of Presentation, and Accounting Policies - Additional Information (Details)

v3.21.1
Business, Basis of Presentation, and Accounting Policies - Additional Information (Details)
$ in Billions
3 Months Ended
Mar. 31, 2021
USD ($)
subsidiary
Dec. 31, 2020
USD ($)
Accounting Policies [Abstract]    
Number of wholly owned subsidiaries | subsidiary 1  
Account balance in trust for investors and escrow balances for mortgagors | $ $ 1.7 $ 1.7