Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating activities:
Net income	$ 117,655	$ 64,814	$ 92,072
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation of premises and equipment, and amortization	6,363	6,453	6,915
Amortization of intangible assets	5,464	5,724	5,723
Provision for (benefit from) credit losses	(6,775)	42,813	(1,690)
Amortization of investment securities premium, net	6,685	2,669	2,547
Gain on sale of investment securities	0	(7)	(110)
Originations of loans for resale	(217,210)	(227,831)	(131,074)
Proceeds from sale of loans originated for resale	227,938	234,424	131,689
Gain on sale of loans	(9,580)	(9,122)	(3,282)
Change in market value of mortgage servicing rights	872	2,634	1,811
Provision for (reversal of) losses on real estate owned	0	128	(102)
Deferred income tax expense	(936)	(14,154)	1,692
Gain on sale or transfer of loans, to real estate owned	(233)	(235)	(608)
Operating lease payments	(4,964)	(4,927)	(4,931)
(Gain) loss on disposal of fixed assets	(439)	67	82
Increase in cash value of life insurance	(2,775)	(2,949)	(3,029)
Gain on life insurance death benefit	(702)	(498)	(831)
(Gain) loss on marketable equity securities	86	(64)	(86)
Equity compensation vesting expense	2,638	2,036	1,654
Change in value of other real estate	9	0	0
Change in:
Interest receivable	712	(1,107)	515
Interest payable	(434)	(1,045)	410
Amortization of operating lease right of use asset	5,452	5,393	4,592
Other assets and liabilities, net	2,381	9,586	(1,153)
Net cash from operating activities	132,207	114,802	102,806
Investing activities:
Proceeds from maturities of securities available for sale	371,632	167,515	97,993
Proceeds from maturities of securities held to maturity	83,929	89,858	68,346
Proceeds from sale of available for sale securities	0	229	127,066
Purchases of securities available for sale	(1,190,690)	(617,552)	(37,253)
Net redemption of restricted equity securities	0	0	0
Loan origination and principal collections, net	(45,812)	(415,415)	(286,339)
Loans purchased	(108,433)	(41,126)	0
Proceeds from sale of real estate owned	1,526	570	1,336
Proceeds from sale of premises and equipment	2,743	0	0
Purchases of premises and equipment	(3,196)	(2,812)	(4,293)
Life insurance proceeds	4,490	2,400	3,355
Net cash from investing activities	(883,811)	(816,333)	(29,789)
Financing activities:
Net change in deposits	861,225	1,138,940	528
Net change in other borrowings	23,173	8,460	2,615
Repurchase of common stock, net	(4,344)	(26,720)	(2,196)
Dividends paid	(29,724)	(26,303)	(24,999)
Exercise of stock options, net	144	198	9
Net cash from financing activities	850,474	1,094,575	(24,043)
Net change in cash and cash equivalents	98,870	393,044	48,974
Cash and cash equivalents at beginning of year	669,551	276,507	227,533
Cash and cash equivalents at end of year	768,421	669,551	276,507
Supplemental disclosure of noncash activities:
Unrealized gain (loss) on securities available for sale	(19,575)	15,796	24,361
Loans transferred to foreclosed assets	1,052	766	1,249
Market value of shares tendered in-lieu of cash to pay for exercise of options and/or related taxes	2,118	736	5,108
Obligations incurred in conjunction with leased assets	2,883	4,161	156
Supplemental disclosure of cash flow activity:
Cash paid for interest expense	5,942	10,502	14,965
Cash paid for income taxes	$ 46,300	$ 29,500	$ 35,050