Fair Value of Assets and Liabilities - Fair Value of Servicing Assets to Adverse Changes in Key Assumptions (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Servicing assets	$ 81,760		$ 84,308
Level 3 Inputs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Servicing assets	81,760		84,308
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Servicing assets	81,760	$ 85,387	84,308	$ 86,518	$ 79,427	$ 67,726
Fair Value, Measurements, Recurring | Level 3 Inputs | Servicing Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Servicing assets	81,760		84,308
Discount rates, impact of 100 basis point increase	(695)		(726)
Discount rates, impact of 200 basis point increase	(1,391)		(1,451)
Expected credit loss on rates on underlying loans, 10% adverse change	(1,026)		(1,037)
Expected credit loss on rates on underlying loans, 20% adverse change	(2,051)		(2,074)
Expected prepayment rates, 10% adverse change	(1,720)		(1,994)
Expected prepayment rates, 20% adverse change	$ (3,440)		$ (3,989)