Allowance for Loss - Sharing Obligations (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Roll forward of loss contingency accrual
Provisions for loss sharing		$ 1,862	$ (6,167)	$ 14,822
Guarantee obligations		34,400	34,400
Impact of adopting CECL		1,100
Allowance for loan and lease loss, recovery of bad debts	$ 1,200
Fannie Mae Mortgage
Roll forward of loss contingency accrual
Allowance for loss sharing obligations		$ 22,700	$ 21,700
Loss-sharing obligations (as a percent)		0.12%	0.11%
Loss-Sharing Obligation
Roll forward of loss contingency accrual
Outstanding advances under the Fannie Mae DUS program		$ 800	$ 100
Loss-Sharing Obligation | Fannie Mae Mortgage
Roll forward of loss contingency accrual
Beginning balance		56,064	64,303
Provisions for loss sharing		3,592	44
Provisions reversal for loan repayments		(1,730)	(6,211)
Recoveries (charge-offs), net		(758)	(2,072)
Ending balance		57,168	56,064	$ 64,303
Maximum quantifiable liability		$ 3,490,000	$ 3,600,000