Mortgage Servicing Rights and Mortgage Servicing Liabilities - Mortgage Servicing Liabilities Carried at FV (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Amortized cost:
Mortgage servicing liabilities resulting from loan sales				$ 98,147
Mortgage servicing liabilities
Amortized cost:
Balance at beginning of period	$ 2,337	$ 100,091	$ 2,816	45,324
Mortgage servicing liabilities resulting from loan sales		33,764		98,147
Changes in valuation inputs used in valuation model	(38)	(54,222)	(305)	(36,375)
Other changes in fair value	(85)	(32,066)	(297)	(59,529)
Total change in fair value	(123)	(86,288)	(602)	(95,904)
Balance at end of period	2,214	47,567	2,214	47,567
UPB of underlying loan at end of period	$ 35,143	$ 8,885,785	$ 35,143	$ 8,885,785