Consolidated Statements Of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Operating Activities
Net Income	$ 61,439,000	$ 69,014,000	$ 59,486,000
Adjustments to reconcile net income to net cash provided by operating activities:
Originations of mortgage loans held for sale	(152,170,000)	(436,740,000)	(654,097,000)
Proceeds from the sale of mortgage loans	156,100,000	484,718,000	640,841,000
Gain on sale of mortgage loans, net of origination costs	(3,403,000)	(13,265,000)	(15,328,000)
Provision (credit) for credit losses	4,500,000	(3,190,000)	12,418,000
Depreciation and amortization expense	3,490,000	3,708,000	3,828,000
Investment securities amortization and accretion, net	3,831,000	6,722,000	4,803,000
Stock-based compensation expense	2,553,000	2,381,000	1,785,000
Amortization of core deposit intangible assets	625,000	655,000	682,000
Purchase accounting accretion, net	(280,000)	(699,000)	(1,304,000)
Net decrease (increase) in derivative collateral posted	31,830,000	26,700,000	(26,540,000)
Net gain on sale of premises	(204,000)	0	0
Net loss (gain) on sale of investment securities	912,000	0	0
Deferred income tax expense (benefit)	1,785,000	(637,000)	(1,761,000)
(Increase) decrease in other assets	(4,063,000)	3,306,000	(9,151,000)
(Decrease) increase in other liabilities	(1,762,000)	43,000	2,568,000
Net cash provided by operating activities	105,183,000	142,716,000	18,230,000
Investing Activities
Proceeds from sales, calls and maturities of available-for-sale debt securities	210,777,000	321,625,000	264,124,000
Purchase of available-for-sale debt securities	(95,421,000)	(758,847,000)	(433,418,000)
Proceeds from maturities of held-to-maturity securities	22,896,000	0	0
Purchase of held-to-maturity securities	42,748,000	0	0
Net increase in loans	(579,363,000)	(211,745,000)	(124,488,000)
Purchase of Federal Home Loan Bank stock	(43,928,000)	(68,000)	(9,231,000)
Proceeds from sale of Federal Home Loan Bank	41,495,000	1,329,000	9,665,000
Purchase of premises and equipment	(2,183,000)	(1,852,000)	(2,926,000)
Proceeds from the sale of premises	466,000	0	0
Proceeds from other investments	0	0	1,712,000
Proceeds from sale of other real estate owned	287,000	465,000	110,000
Net cash used in investing activities	(487,722,000)	(649,093,000)	(294,452,000)
Financing Activities
Net increase in deposits	218,040,000	603,645,000	467,519,000
Net proceeds from (repayments of) borrowings less than 90 days	53,568,000	49,169,000	(106,370,000)
Proceeds from Federal Home Loan Bank long-term advances	0	0	25,000,000
Repayments of Federal Home Loan Bank long-term advances	0	(25,000,000)	(10,000,000)
Repayment of subordinated debt	0	(15,000,000)	0
Common stock repurchases	(10,240,000)	(10,090,000)	(9,689,000)
Exercise of stock options and issuance of restricted stock, net of repurchase for tax withholdings	(355,000)	(263,000)	(116,000)
Cash dividends paid on common stock	(23,512,000)	(21,081,000)	(19,842,000)
Finance lease payments	(160,000)	(152,000)	(142,000)
Net cash provided by financing activities	237,341,000	581,228,000	346,360,000
Net (decrease) increase in cash, cash equivalents and restricted cash	(145,198,000)	74,851,000	70,138,000
Cash, cash equivalents and restricted cash at beginning of year	220,625,000	145,774,000	75,636,000
Cash, cash equivalents and restricted cash at end of year	75,427,000	220,625,000	145,774,000
Supplemental information
Transfer from available-for-sale securities to held-to-maturity securities (Note 2)	520,335,000	0	0
Interest paid	24,547,000	11,192,000	21,505,000
Income taxes paid	13,237,000	18,502,000	15,660,000
Cash dividends declared, not paid	6,134,000	5,959,000	4,936,000
Transfer from premises to other real estate owned	0	204,000	24,000
Transfer from loans to other real estate owned	0	0	236,000
Unsettled common stock repurchase	$ 0	$ 0	$ 11,000