Consolidated Statements of Cash Flows - USD ($)		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022		Dec. 31, 2021
Cash flows from operating activities:
Net income		$ 71,104,000	$ 78,120,000		$ 91,801,000
Adjustments to reconcile net income to net cash provided by operating activities:
Provision (reversal of provision) for credit losses		10,770,000	12,198,000		(10,132,000)
Depreciation of premises and equipment		5,057,000	4,465,000		4,662,000
Net gain on sales of investment securities		0	(30,000)	[1]	(145,000)	[1]
Net gain on mortgage banking activities	[1]	(3,689,000)	(4,412,000)		(15,141,000)
Bank owned life insurance income	[1]	(3,185,000)	(3,787,000)		(3,981,000)
Net amortization of investment securities premiums and discounts		1,138,000	1,462,000		2,676,000
Amortization, fair market value adjustments and capitalization of servicing rights		(411,000)	(693,000)		(1,470,000)
Net amortization (accretion) of acquisition accounting fair value adjustments		25,000	(130,000)		(144,000)
Stock-based compensation		4,194,000	4,120,000		3,698,000
Intangible expenses		938,000	1,293,000		979,000
Other adjustments to reconcile net income to cash used in by operating activities		(1,487,000)	(4,094,000)		(4,963,000)
Deferred tax (benefit) expense		(710,000)	(545,000)		3,553,000
Originations of loans held for sale		(228,532,000)	(233,634,000)		(495,710,000)
Proceeds from the sale of loans held for sale		226,506,000	255,240,000		527,855,000
Contributions to pension and other postretirement benefit plans		(250,000)	(252,000)		(265,000)
Increase in accrued interest receivable and other assets		(8,877,000)	(5,859,000)		(3,131,000)
Increase in accrued interest payable and other liabilities		17,150,000	5,993,000		2,195,000
Net cash provided by operating activities		89,741,000	109,455,000		102,337,000
Cash flows from investing activities:
Net cash paid due to acquisitions		0	0		(3,820,000)
Proceeds from sale of premises and equipment		1,877,000	6,845,000		0
Purchases of premises and equipment		(6,724,000)	(5,221,000)		(5,878,000)
Proceeds from maturities, calls and principal repayments of securities held-to-maturity		14,799,000	32,021,000		64,583,000
Proceeds from maturities, calls and principal repayments of securities available-for-sale		30,738,000	31,600,000		50,431,000
Proceeds from sales		0	1,530,000		4,636,000
Purchases of investment securities held-to-maturity		(6,253,000)	(10,428,000)		(91,979,000)
Purchases of investment securities available-for-sale		(25,132,000)	(116,599,000)		(154,270,000)
Proceeds from sales of money market mutual funds		1,232,000	4,015,000		7,328,000
Purchases of money market mutual funds		(1,963,000)	(3,793,000)		(6,887,000)
Net increase in other investments		(6,658,000)	(5,655,000)		(3,000)
Proceeds from sale of loans originally held-for-investment		25,450,000	2,500,000		996,000
Net increase in loans and leases		(474,200,000)	(836,616,000)		(2,171,000)
Proceeds from sales of other real estate owned		260,000	0		7,255,000
Purchases of bank owned life insurance		(7,862,000)	0		0
Proceeds from bank owned life insurance		0	2,189,000		3,000,000
Net cash used in investing activities		(454,436,000)	(897,612,000)		(126,779,000)
Cash flows from financing activities:
Net increase (decrease) in deposits		462,229,000	(141,628,000)		812,375,000
Net (decrease) increase in short-term borrowings		(190,835,000)	177,035,000		2,200,000
Proceeds from issuance of long-term debt		250,000,000	0		0
Repayment of long-term debt		(35,000,000)	0		(15,000,000)
Proceeds from issuance of subordinated notes		0	50,000,000		0
Subordinated notes issuance costs		0	(949,000)		0
Repayment of subordinated notes		0	0		(85,000,000)
Payment of contingent consideration on acquisitions		(635,000)	0		(58,000)
Payment for shares withheld to cover taxes on vesting of restricted stock units		(1,232,000)	(903,000)		(355,000)
Purchases of treasury stock		(462,000)	(11,381,000)		(295,000)
Stock issued under dividend reinvestment and employee stock purchase plans		2,565,000	2,541,000		2,384,000
Proceeds from exercise of stock options		115,000	698,000		2,058,000
Cash dividends paid		(25,050,000)	(24,607,000)		(23,575,000)
Net cash provided by financing activities		461,695,000	50,806,000		694,734,000
Net increase (decrease) in cash and cash equivalents		97,000,000	(737,351,000)		670,292,000
Cash and cash equivalents at beginning of year		152,799,000	890,150,000		219,858,000
Cash and cash equivalents at end of year		249,799,000	152,799,000		890,150,000
Supplemental disclosures of cash flow information:
Cash paid for interest		139,600,000	32,668,000		21,824,000
Cash paid for income taxes, net of refunds		16,784,000	11,859,000		26,589,000
Non cash transactions:
Transfer of loans to other real estate owned		79,000	18,325,000		126,000
Transfer of loans to loans held for sale		25,646,000	2,500,000		996,000
Contingent consideration recorded as goodwill		$ 0	$ 0		$ 1,618,000

[1] Net interest income as well as many other revenues for financial assets and liabilities including loans, leases, securities, and derivatives are excluded from the scope of FASB ASC 606 "Revenue from Contracts with Customers" ("FASB ASC 606"). Noninterest income streams that are out of scope of FASB ASC 606 include bank owned life insurance income, sales of investment securities and mortgage banking activities.