Fair Value Measurements - Reconciliation of Assets with Unobservable Inputs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 13,907	$ 10,150	$ 12,829	$ 8,178
Change included in earnings	(1,236)	(688)	(3,836)	(1,834)
Purchases and issuances	5,641	5,731	15,537	16,787
Sales and settlements	(4,725)	(4,381)	(10,943)	(12,319)
Ending balance	13,587	10,812	13,587	10,812
Net change in unrealized gains (losses) relating to items held at end of period	1,363	1,117	1,363	1,117
Interest rate lock commitments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	2,072	1,417	978	873
Change included in earnings	(553)	(560)	(1,431)	(1,562)
Purchases and issuances	4,569	4,641	12,759	14,125
Sales and settlements	(4,725)	(4,381)	(10,943)	(12,319)
Ending balance	1,363	1,117	1,363	1,117
Net change in unrealized gains (losses) relating to items held at end of period	1,363	1,117	1,363	1,117
Mortgage servicing rights
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	10,836	8,733	10,821	7,305
Change included in earnings	(663)	(128)	(2,287)	(272)
Purchases and issuances	1,033	1,090	2,672	2,662
Sales and settlements	0	0	0	0
Ending balance	11,206	9,695	11,206	9,695
Net change in unrealized gains (losses) relating to items held at end of period	0	$ 0	0	$ 0
Commercial servicing rights
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	999		1,030
Change included in earnings	(20)		(118)
Purchases and issuances	39		106
Sales and settlements	0		0
Ending balance	1,018		1,018
Net change in unrealized gains (losses) relating to items held at end of period	$ 0		$ 0