Fair Value Measurements - Reconciliation of Assets with Unobservable Inputs (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 17,171,000	$ 16,536,000	$ 16,562,000	$ 13,944,000
Change included in earnings	(2,383,000)	(3,390,000)	(6,049,000)	(9,466,000)
Purchases and issuances	9,175,000	16,927,000	28,877,000	43,725,000
Sales and settlements	(6,357,000)	(11,679,000)	(21,784,000)	(29,809,000)
Ending balance	17,606,000	18,394,000	17,606,000	18,394,000
Net change in unrealized gains (losses) relating to items held at end of period	3,248,000	6,519,000	3,248,000	6,519,000
Net change in unrealized gains (losses) included in other comprehensive income	0	0	0	0
Mortgage servicing rights
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	12,835,000	10,721,000	11,218,000	11,920,000
Change included in earnings	(1,458,000)	(1,505,000)	(3,034,000)	(4,363,000)
Purchases and issuances	1,703,000	1,373,000	4,896,000	3,032,000
Sales and settlements	0	0	0	0
Ending balance	13,080,000	10,589,000	13,080,000	10,589,000
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	1,292,000	1,162,000	1,310,000	1,214,000
Change included in earnings	(58,000)	(101,000)	(134,000)	(180,000)
Purchases and issuances	44,000	225,000	102,000	252,000
Sales and settlements	0	0	0	0
Ending balance	1,278,000	1,286,000	1,278,000	1,286,000
Net change in unrealized gains (losses) relating to items held at end of period	0	0	0	0
Interest rate lock commitments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	3,044,000	4,653,000	4,034,000	810,000
Change included in earnings	(867,000)	(1,784,000)	(2,881,000)	(4,923,000)
Purchases and issuances	7,428,000	15,329,000	23,879,000	40,441,000
Sales and settlements	(6,357,000)	(11,679,000)	(21,784,000)	(29,809,000)
Ending balance	3,248,000	6,519,000	3,248,000	6,519,000
Net change in unrealized gains (losses) relating to items held at end of period	$ 3,248,000	$ 6,519,000	$ 3,248,000	$ 6,519,000