Mortgage banking activities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Mortgage servicing rights fair value adjustments			$ (10,280)	$ (11,135)
Net gain (loss) on sale of loans, including valuation on loans held-for-sale	$ 0	$ (44)	0	(44)
Total trading account (loss) profit	817	219	1,455	632
Total mortgage banking activities	2,670	5,393	12,753	15,109
Mortgage banking activities
Mortgage servicing fees	7,559	8,025	22,912	25,083
Mortgage servicing rights fair value adjustments	(4,896)	(2,793)	(10,280)	(10,385)
Total mortgage servicing fees, net of fair value adjustments	2,663	5,232	12,632	14,698
Net gain (loss) on sale of loans, including valuation on loans held-for-sale	320	(335)	396	(133)
Unrealized (loss) gains on outstanding derivative positions	(44)	45	113	160
Realized (loss) gains on closed derivative positions	(261)	494	(249)	661
Total trading account (loss) profit	(305)	539	(136)	821
Losses on repurchased loans, including interest advances	(8)	(43)	(139)	(277)
Total mortgage banking activities	$ 2,670	$ 5,393	$ 12,753	$ 15,109