Mortgage Servicing Rights - Estimated Future Amortization Expenses (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Other Intangible Assets
Unpaid principal amount of consumer loans serviced for others	$ 1,400,000		$ 1,400,000		$ 1,400,000
Contractually specified fees, late charges, and ancillary fees	800	$ 1,000	1,700	$ 2,000
Amortization of mortgage servicing rights	278	$ 518	558	$ 1,255
Details of MSRs
Gross carrying amount	69,341		69,341		69,273
Less: accumulated amortization	63,269		63,269		62,711
Net carrying value	6,072		6,072		$ 6,562
Mortgage servicing assets
Estimated future amortization expenses for MSRs over the next five years
Under one year	885		885
One to two years	786		786
Two to three years	696		696
Three to four years	614		614
Four to five years	$ 542		$ 542