Servicing Rights - Mortgage Servicing Rights (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Changes in fair value:
Balance of mortgage loans serviced for others	$ 750,327		$ 750,327		$ 683,117
MSR as a percentage of serviced loans	1.74%		1.74%		1.64%
Mortgage servicing rights
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance, beginning of period	$ 12,835	$ 10,721	$ 11,218	$ 11,920
Additions for new MSR capitalized	1,703	1,373	4,896	3,032
Changes in fair value:
Due to changes in model inputs of assumptions	(928)	(699)	(1,092)	(2,291)
Other	(530)	(806)	(1,942)	(2,072)
Balance, end of period	13,080	$ 10,589	13,080	$ 10,589
Balance of mortgage loans serviced for others	$ 750,327		$ 750,327		$ 683,117
MSR as a percentage of serviced loans	1.74%		1.74%		1.64%