Guarantees - Credit recourse - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Jun. 30, 2024	Dec. 31, 2023	Jun. 30, 2023	Dec. 31, 2022
Guarantee on loans sold or serviced with credit recourse
Guarantor Obligations [Line Items]
Valuation allowances and reserves balance	$ 3,196	$ 6,397	$ 3,196	$ 6,397	$ 4,058	$ 4,211	$ 6,223	$ 6,897
Serviced mortgage loans
Guarantor Obligations [Line Items]
Loans serviced	9,200,000		9,200,000			9,900,000
Loans with recourse | Serviced mortgage loans
Guarantor Obligations [Line Items]
Repurchased loans	500	400	1,500	2,000
Loans with recourse | Residential mortgage loans
Guarantor Obligations [Line Items]
Loans serviced	$ 511,000	$ 561,000	$ 511,000	$ 561,000		$ 561,000