Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019
Cash flows from operating activities:
Net income		$ 38,638	$ 43,933
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation		3,003	2,958
Amortization of right-of-use asset		4,588	4,420
Net gain on sale of other real estate owned		(332)	(686)
Writedown of other real estate owned		120	294
Provision (credit) for loan losses		5,000	(41)
Deferred tax (benefit) expense		(1,199)	844
Net amortization of securities		2,703	2,128
Stock based compensation expense		14	0
Net gain on sale of bank premises and equipment		0	(3)
Net gain on sales of securities	[1]	(1,155)	0
Decrease in taxes receivable		570	1,903
Increase in interest receivable		(180)	(397)
(Decrease) increase in interest payable		(682)	510
Increase in other assets		(1,201)	(2,669)
Decrease in operating lease liabilities		(4,715)	(4,489)
Increase in accrued expenses and other liabilities		2,734	1,066
Total adjustments		9,268	5,838
Net cash provided by operating activities		47,906	49,771
Cash flows from investing activities:
Proceeds from sales and calls of securities available for sale		226,886	101,306
Proceeds from calls and maturities of held to maturity securities		3,398	2,665
Purchases of securities available for sale		(103,991)	(260,466)
Proceeds from maturities of securities available for sale		5,000	10,052
Purchases of Federal Reserve Bank and Federal Home Loan Bank stock		(380)	(230)
Proceeds from redemption of Federal Reserve Bank stock		4,057	0
Net increase in loans		(152,987)	(115,120)
Proceeds from dispositions of other real estate owned		1,802	3,159
Proceeds from dispositions of bank premises and equipment		0	3
Purchases of bank premises and equipment		(2,798)	(2,432)
Net cash used in investing activities		(19,013)	(261,063)
Cash flows from financing activities:
Net increase in deposits		449,034	186,920
Net increase (decrease) in short-term borrowings		44,789	(10,798)
Proceeds from exercise of stock options		0	153
Proceeds from sale of treasury stock		0	1,791
Purchases of treasury stock		(3,493)	(35)
Dividends paid		(19,750)	(19,771)
Net cash provided by financing activities		470,580	158,260
Net increase (decrease) in cash and cash equivalents		499,473	(53,032)
Cash and cash equivalents at beginning of period		456,846	503,709
Cash and cash equivalents at end of period		956,319	450,677
Cash paid during the year for:
Interest paid		21,451	26,529
Income taxes paid		12,274	12,263
Other non cash items:
Transfer of loans to other real estate owned		434	3,501
Increase in dividends payable		214	17
Change in unrealized gain on securities available for sale-gross of deferred taxes		10,237	14,185
Change in deferred tax effect on unrealized gain on securities available for sale		(2,660)	(3,686)
Amortization of net actuarial gain and prior service credit on pension and postretirement plans		(678)	(353)
Change in deferred tax effect of amortization of net actuarial gain postretirement benefit plans		$ 177	$ 92

[1] Not within the scope of ASC 606.