Servicing Rights - Mortgage Servicing Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance, beginning of period	$ 10,821
Additions for new MSR capitalized	1,107	$ 760
Changes in fair value:
Balance, end of period	11,254
Balance of mortgage loans serviced for others	$ 586,595		$ 557,583
MSR as a percentage of serviced loans	1.92%		1.94%
Mortgage servicing rights
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance, beginning of period	$ 10,821	7,305
Additions for new MSR capitalized	1,107	760
Changes in fair value:
Due to changes in model inputs of assumptions	(377)	255
Other	(297)	(281)
Balance, end of period	11,254	$ 8,039
Balance of mortgage loans serviced for others	$ 586,595		$ 557,583
MSR as a percentage of serviced loans	1.92%		1.94%