Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Statement of Cash Flows [Abstract]
Net income	$ 205,122,000	$ 192,081,000	$ 239,502,000
Depreciation, Depletion and Amortization, Nonproduction	42,142,000	40,889,000	36,102,000
Change In Unamortized Net Loan Costs And Premiums	(1,979,000)	(1,739,000)	(1,856,000)
Accretion of acquired loans	(11,530,000)	(538,000)	(2,251,000)
Provision for credit losses	65,469,000	36,250,000	23,250,000
Deferred income tax (benefit) expense	(3,283,000)	(10,600,000)	2,738,000
Equity Securities, FV-NI, Gain (Loss)	(403,000)	(423,000)	(1,180,000)
Gain (Loss) on Investments	64,000
Gain (Loss) on Disposition of Property Plant Equipment	130,000	155,000	310,000
Sale and Leaseback Transaction, Gain (Loss), Net	0	0	193,000
Share-based Payment Arrangement, Noncash Expense	8,985,000	6,523,000	6,377,000
Life Insurance, Corporate or Bank Owned, Change in Value	(9,434,000)	(8,086,000)	(7,877,000)
Gain Realized on Life Insurance Policies	(1,965,000)	(457,000)	(2,291,000)
Operating Lease, Payments	(15,339,000)	(14,018,000)	(13,863,000)
Increase (Decrease) in Loans Held-for-sale	457,000	(20,000)	97,000
Increase (Decrease) in Debt Securities, Trading, and Equity Securities, FV-NI	(475,000)	742,000	(1,099,000)
Increase (Decrease) in Loans Held-for-sale	(27,931,000)	(923,000)	(3,468,000)
Increase (Decrease) in Other Operating Assets	72,162,000	(15,498,000)	23,504,000
Change in other liabilities	(70,118,000)	5,543,000	(20,614,000)
Total adjustments	46,038,000	37,840,000	37,492,000
Net cash provided by operating activities	251,160,000	229,921,000	276,994,000
Increase (Decrease) in Equity Securities, FV-NI	(984,000)	(1,058,000)	(742,000)
Proceeds from Sale of Debt Securities, Available-for-sale	74,303,000	0	0
Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-sale	254,799,000	235,144,000	106,713,000
Payments to Acquire Debt Securities, Available-for-sale	(426,161,000)	(129,379,000)	0
Proceeds from maturities and principal repayments of securities held to maturity	161,164,000	138,399,000	140,888,000
Net decrease (increase) in Federal Home Loan Bank stock	16,621,000	11,984,000	(38,339,000)
Investments in low-income housing projects	(38,722,000)	(33,053,000)	(31,073,000)
Purchases of life insurance policies	(117,000)	(114,000)	(162,000)
Proceeds from Life Insurance Policy	3,951,000	1,929,000	5,531,000
Payments for (Proceeds from) Loans and Leases	(125,724,000)	(236,519,000)	(378,735,000)
Cash Acquired in Excess of Payments to Acquire Business	97,760,000	0	0
Payments to Acquire Property, Plant, and Equipment	(12,135,000)	(20,435,000)	(15,844,000)
Proceeds from Sale of Property, Plant, and Equipment	295,000	92,000	113,000
Net cash provided by (used in) investing activities	5,050,000	(33,010,000)	(211,650,000)
Increase (Decrease) in Time Deposits	(219,128,000)	565,752,000	985,567,000
Increase (Decrease) in Other Deposits	677,185,000	(125,436,000)	(1,999,198,000)
Increase (Decrease) in Federal Funds Purchased and Securities Sold under Agreements to Repurchase, Net	(284,373,000)	(467,000,000)	1,105,000,000
Proceeds from Lines of Credit	49,937,000	0	0
Proceeds from Issuance of Subordinated Long-term Debt	295,843,000	0	0
Repayments of Subordinated Debt	(60,000,000)	(50,000,000)	0
Cash received from stock option exercises	0	80,000	80,000
Issuance Of Restricted Stock Awards, Net of Issuance Cost	(1,459,000)	(815,000)	(1,142,000)
Proceeds from shares issued under direct stock purchase plan	2,549,000	3,254,000	2,662,000
Payments for Repurchase of Common Stock	(60,849,000)	(30,986,000)	(188,910,000)
Common dividends paid	(103,903,000)	(96,200,000)	(98,006,000)
Net cash provided by (used in) financing activities	295,802,000	(201,351,000)	(193,947,000)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect, Total	552,012,000	(4,440,000)	(128,603,000)
Cash and cash equivalents at beginning of year	219,890,000	224,330,000	352,933,000
Cash and cash equivalents at end of period	771,902,000	219,890,000	224,330,000
Supplemental schedule of non-cash investing and financing activities
Interest Paid, Excluding Capitalized Interest, Operating Activity	307,257,000	291,692,000	183,068,000
Income taxes	34,783,000	51,079,000	43,706,000
Real Estate Owned, Transfer from Real Estate Owned	2,100,000	0	0
Capital commitment relating to Low Income Housing Project investments, noncash	67,251,000	46,070,000	31,891,000
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	23,075,000	12,602,000	7,916,000
In conjunction with the Company's acquisitions, assets were acquired and liabilities were assumed as follows
Common stock issued for acquisition	477,266,000
Fair value of assets acquired, net of cash acquired	4,930,778,000	0	0
Fair value of liabilities assumed	$ 4,551,272,000	$ 0	$ 0