Capital and Liquidity Requirements (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Compliance with Regulatory Capital Requirements under Banking Regulations
Percentage of Freddie Mac's liquidity requirement of outstanding principal of TAH loans serviced	8.00%	8.00%
Other Assets
Compliance with Regulatory Capital Requirements under Banking Regulations
Outstanding borrower advances	$ 1.1		$ 0.9
Seller/Servicer Agreements
Compliance with Regulatory Capital Requirements under Banking Regulations
Amount of capital in excess of aggregate regulatory requirements	$ 459.1		$ 400.5