Guarantees - Credit recourse - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022	Dec. 31, 2021
Guarantee on loans sold or serviced with credit recourse
Guarantor Obligations
Valuation allowances and reserves balance	$ 6,397	$ 7,193	$ 6,397	$ 7,193	$ 6,223	$ 6,897	$ 9,095	$ 11,800
Serviced mortgage loans
Guarantor Obligations
Loans serviced	10,100,000		10,100,000			11,100,000
Loans with recourse
Guarantor Obligations
Loans serviced	600,000		600,000			$ 600,000
Loans with recourse | Serviced mortgage loans
Guarantor Obligations
Repurchased loans	$ 400	$ 1,000	$ 2,000	$ 6,000