CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Cash Flows Provided by (Used in) Operating Activities
Net income	$ 128,311	$ 123,449	$ 100,344
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Provision for credit losses	4,623	(15,101)	38,797
Amortization of intangible assets	11,628	11,274	10,008
Amortization of mortgage servicing rights	3,540	5,292	5,667
Amortization of NMTC	6,333	5,563	2,311
Depreciation and amortization of premises and equipment	10,482	11,610	12,273
Net amortization (accretion) on portfolio loans	3,932	(11,545)	(15,372)
Net amortization (accretion) of premium (discount) on investment securities	20,799	24,251	9,716
Net amortization (accretion) of premium (discount) on time deposits	(403)	(1,142)	(933)
Net amortization (accretion) of premium (discount) on FHLB advances and other borrowings	1,400	826	586
Impairment of OREO and other repossessed assets	611	1	68
Impairment of fixed assets held for sale	427	3,227	6,901
Impairment of mortgage servicing rights	(8)	(639)	648
Impairment of leases	84	0	0
Unrealized (gains) losses recognized on equity securities, net	2,183	(3,041)	393
(Gain) loss on sales of equity securities, net	(24)	0	0
(Gain) loss on sales of debt securities, net	(26)	(29)	(1,724)
(Gain) loss on sales of loans, net	(1,944)	(9,323)	(26,999)
(Gain) loss on sales of OREO	(54)	174	(133)
(Gain) loss on sales of premises and equipment	(825)	(1,023)	286
(Gain) loss on life insurance proceeds	0	(1,257)	(1,270)
(Increase) decrease in cash surrender value of bank owned life insurance	(3,663)	(3,909)	(4,110)
Provision for deferred income taxes	(1,272)	4,665	(5,309)
Stock-based compensation	8,968	7,864	7,135
Mortgage loans originated for sale	(70,953)	(274,356)	(881,398)
Proceeds from sales of mortgage loans	95,289	306,074	920,050
(Increase) decrease in other assets	(56,284)	7,203	(8,210)
Increase (decrease) in other liabilities	2,633	(28,096)	(6,551)
Net cash provided by (used in) operating activities	165,787	162,012	163,174
Cash Flows Provided by (Used in) Investing Activities
Purchases of equity securities	(14,820)	(11,017)	(13,123)
Purchases of debt securities available for sale	(280,083)	(2,298,055)	(1,282,199)
Proceeds from sales of equity securities	15,418	7,254	13,152
Proceeds from sales of debt securities available for sale	0	290,955	0
Proceeds from paydowns and maturities of debt securities held to maturity	70,116	0	0
Proceeds from paydowns and maturities of debt securities available for sale	470,134	868,083	665,744
Purchases of FHLB and other bank stock	(12,969)	0	0
Proceeds from the redemption of FHLB and other bank stock	225	0	0
Net cash received in (paid for) acquisitions (see Note 2)	0	228,279	0
Net (increase) decrease in loans	(541,713)	76,826	(113,744)
Cash paid for premiums on bank-owned life insurance	(106)	(124)	(120)
Proceeds from life insurance	219	4,755	2,696
Purchases of premises and equipment	(4,989)	(5,042)	(4,198)
Proceeds from disposition of premises and equipment	4,528	7,306	814
Proceeds from sales of OREO	3,184	1,590	1,439
Net cash provided by (used in) investing activities	(290,856)	(829,190)	(729,539)
Cash Flows Provided by (Used in) Financing Activities
Net increase (decrease) in deposits	(696,894)	767,474	776,386
Net change in federal funds purchased and securities sold under agreements to repurchase	(40,333)	77,874	(29,877)
Proceeds from FHLB advances	335,000	5,000	4,000
Repayment of FHLB advances	(5,678)	(4,658)	(32,711)
Proceeds from other borrowings, net of debt issuance costs	98,094	72,500	142,634
Repayment of other borrowings	(112,000)	(18,500)	(74,000)
Cash dividends paid	(50,863)	(50,764)	(48,012)
Purchase of treasury stock	(9,912)	(33,043)	(12,272)
Cash paid for withholding taxes on stock-based payments	(1,276)	(997)	(635)
Proceeds from stock options exercised	0	0	101
Common stock issuance costs	0	(150)	0
Net cash provided by (used in) financing activities	(483,862)	814,736	725,614
Net increase (decrease) in cash and cash equivalents	(608,931)	147,558	159,249
Cash and cash equivalents, beginning of period	836,095	688,537	529,288
Cash and cash equivalents, ending of period	227,164	836,095	688,537
Cash payments for:
Interest	35,297	25,374	53,601
Income taxes	30,676	22,487	22,195
Non-cash investing and financing activities:
OREO acquired in settlement of loans	175	1,610	2,867
Transfer of loans held for sale to portfolio loans	0	(4,808)	0
Transfer of debt securities available for sale to held to maturity	$ 985,199	$ 0	$ 0