Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating Activities
Net income	$ 87,091	$ 68,499	$ 66,538
Items not requiring (providing) cash
Credit loss expense (recovery)	(2,084)	20,751	1,976
Depreciation and amortization	11,169	10,589	9,688
Share based compensation	68	132	215
Mortgage servicing rights income	226	(737)	(2,106)
Mortgage servicing rights, net impairment	(2,578)	4,453	192
Premium amortization on securities, net	10,289	9,067	5,929
Loss (gain) on sale of investment securities	(914)	(4,297)	75
Gain on sale of mortgage loans	(19,163)	(26,721)	(9,208)
Proceeds from sales of loans	458,255	601,336	275,809
Loans originated for sale	(438,133)	(584,065)	(269,651)
Change in cash value life insurance	(2,094)	(2,243)	(2,190)
Loss (gain) on other real estate owned	(85)	(197)	(126)
Net change in:
Interest receivable	(4,222)	(2,568)	(2,101)
Interest payable	(493)	(350)	205
Other assets	10,964	(13,987)	99,735
Other liabilities	(2,948)	(897)	(608)
Net cash provided by operating activities	105,348	78,765	174,372
Investing Activities
Purchases of securities available for sale	(837,684)	(590,305)	(425,879)
Proceeds from sales, maturities, calls and principal repayments of securities available for sale	287,714	318,897	248,422
Purchases of securities held to maturity	(931,029)	0	0
Proceeds from maturities of securities held to maturity	30,544	37,529	8,384
Net change in interest–earning time deposits	4,183	(510)	7,289
Change in Federal Reserve and FHLB stock	(1,417)	(576)	(803)
Net change in loans	469,412	(234,166)	(59,420)
Proceeds on the sale of OREO and repossessed assets	1,286	2,047	4,744
Change in premises and equipment, net	(1,440)	(5,866)	(4,612)
Death benefit on bank owned life insurance	783	264	580
Repurchase of outstanding stock	(7,607)	(19,636)	(1,595)
Net cash used in investing activities	(363,076)	(492,322)	(94,145)
Net change in:
Deposits	425,449	600,131	50,282
Borrowings	201,137	(74,725)	(71,040)
Proceeds from issuance of stock	(293)	1,390	1,705
Net proceeds from issuance of subordinated notes	0	58,824	0
Dividends paid on common stock	(24,768)	(21,183)	(20,835)
Net cash provided by (used in) financing activities	601,525	564,437	(39,888)
Net Change in Cash and Cash Equivalents	343,797	150,880	40,339
Cash and Cash Equivalents, Beginning of Period	249,711	98,831	58,492
Cash and Cash Equivalents, End of Period	593,508	249,711	98,831
Single Branch
Investing Activities
Net cash received in acquisition, Salin	622,179	0	0
Salin
Investing Activities
Net cash received in acquisition, Salin	$ 0	$ 0	$ 128,745