Loan Sales and Servicing Activities - Geographical Distribution of Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Loan Sales and Servicing Activities
Total loans serviced	$ 564,474,398	$ 551,674,682
California
Loan Sales and Servicing Activities
Total loans serviced	68,843,138	68,542,279
Florida
Loan Sales and Servicing Activities
Total loans serviced	53,021,329	50,873,961
Texas
Loan Sales and Servicing Activities
Total loans serviced	50,400,689	47,911,696
Virginia
Loan Sales and Servicing Activities
Total loans serviced	33,897,358	33,478,151
Maryland
Loan Sales and Servicing Activities
Total loans serviced	25,719,847	25,473,417
All other states
Loan Sales and Servicing Activities
Total loans serviced	$ 332,592,037	$ 325,395,178