Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net Income	$ 161,768	$ 122,034	$ 86,509
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization/accretion	11,774	16,565	16,617
Reversal of Provision for Credit Losses	(1,150)	0	0
Net amortization of deferred loan fees	(573)	(1,704)	(5,576)
Stock option compensation expense	1,356	1,309	1,419
Life insurance gains	(279)	(930)	0
Securities losses (gains)	125	0	(34)
Net changes in:
Interest income receivable	(1,010)	(18,037)	(2,499)
Net deferred taxes	(1,995)	697	3,899
Other assets	(3,443)	(2,415)	(3,534)
Income taxes payable	(869)	3,020	(1,054)
Interest expense payable	(12)	(10)	(72)
Other liabilities	(7,484)	(6,827)	(6,940)
Net Cash Provided by Operating Activities	158,208	113,702	88,735
Investing Activities:
Net repayments of loans	90,192	108,107	193,755
Proceeds from life insurance policies	604	3,041	0
Purchases of debt securities available for sale	0	(636,228)	(1,909,370)
Proceeds from sale/maturity/calls of debt securities available for sale	416,447	500,160	1,204,455
Purchases of debt securities held to maturity	0	(718,940)	0
Proceeds from maturity/calls of debt securities held to maturity	43,518	111,059	206,400
Purchase of Federal Reserve Bank stock	(2,326)	0	0
Proceeds from redemption of Federal Reserve Bank stock	0	2,326	0
Purchases of premises and equipment	(1,161)	(811)	(1,324)
Net Cash Provided by (Used in) Investing Activities	547,274	(631,286)	(306,084)
Financing Activities:
Net change in deposits	(751,023)	(188,666)	725,977
Net change in short-term borrowings	370	(88,454)	43,701
Exercise of stock options	950	2,255	3,017
Retirement of common stock	(13,747)	(218)	(232)
Common stock dividends paid	(45,954)	(45,182)	(44,304)
Net Cash (Used in) Provided by Financing Activities	(809,404)	(320,265)	728,159
Net Change In Cash and Due from Banks	(103,922)	(837,849)	510,810
Cash and Due from Banks at Beginning of Period	294,236	1,132,085	621,275
Cash and Due from Banks at End of Period	190,314	294,236	1,132,085
Supplemental disclosure of noncash activities:
Right-of-use assets acquired in exchange for operating lease liabilities	8,866	3,533	5,105
Supplemental disclosure of cash flow activities:
Cash paid for amounts included in operating lease liabilities	6,217	6,037	6,309
Interest paid for the period	3,902	1,935	2,027
Income tax payments for the period	$ 64,017	$ 39,840	$ 27,673