Consolidated Statements of Cash Flows - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities:
Net income		$ 65,719	$ 50,543	$ 44,094
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan and lease losses		8,518	20,310	9,892
Depreciation of premises and equipment		5,277	5,581	5,561
Net gain on sales of investment securities	[1]	(54)	(10)	(48)
Net gain on mortgage banking activities	[1]	(3,946)	(3,125)	(4,023)
Bank owned life insurance income	[1]	(3,179)	(3,174)	(3,988)
Net amortization of investment securities premiums and discounts		1,738	1,602	1,838
Amortization, fair market value adjustments and capitalization of servicing rights		141	(196)	(87)
Net accretion of acquisition accounting fair value adjustments		(761)	(1,037)	(3,022)
Stock-based compensation		2,348	2,557	3,166
Intangible expenses		1,595	2,166	2,582
Other adjustments to reconcile net income to cash (used in) provided by operating activities		(1,642)	305	(80)
Deferred tax (benefit) expense		(1,807)	(599)	7,483
Originations of loans held for sale		(227,083)	(158,097)	(188,072)
Proceeds from the sale of loans held for sale		227,473	161,357	196,813
Contributions to pension and other postretirement benefit plans		(266)	(3,264)	(2,295)
(Increase) decrease in accrued interest receivable and other assets		(2,332)	4,547	(1,369)
Increase in accrued interest payable and other liabilities		1,409	6,540	215
Net cash provided by operating activities		73,148	86,006	68,660
Cash flows from investing activities:
Net capital expenditures		(2,446)	(3,119)	(3,961)
Proceeds from maturities, calls and principal repayments of securities held-to-maturity		34,207	11,526	23,265
Proceeds from maturities, calls and principal repayments of securities available-for-sale		67,020	54,702	64,954
Proceeds from sales of securities available-for-sale		26,494	1,010	7,069
Purchases of investment securities held-to-maturity		84,733	99,132	54,149
Purchases of investment securities available-for-sale		(2,993)	(1,986)	(33,334)
Proceeds from sales of money market mutual funds		5,035	11,225	29,948
Purchases of money market mutual funds		(5,413)	(6,482)	(25,149)
Net decrease (increase) in other investments		83	(1,133)	(2,335)
Net increase in loans and leases		(381,343)	(398,240)	(338,481)
Proceeds from sales of other real estate owned		720	490	3,996
Purchases of bank owned life insurance		0	(1,563)	(7,271)
Proceeds from bank owned life insurance		0	1,384	2,961
Net cash used in investing activities		(343,369)	(431,318)	(332,487)
Cash flows from financing activities:
Net increase in deposits		474,190	331,170	297,792
Net (decrease) increase in short-term borrowings		(171,088)	84,337	(90,740)
Proceeds from issuance of long-term debt		25,000	10,000	95,000
Repayments of long-term debt		(20,000)	(20,000)	(65,000)
Payment of contingent consideration on acquisitions		(129)	(131)	(5,413)
Proceeds from public offering of common stock		0	0	70,501
Purchases of treasury stock		(2,045)	(5,984)	(3,519)
Stock issued under dividend reinvestment and employee stock purchase plans		2,233	2,295	2,413
Proceeds from exercise of stock options		1,203	1,131	1,676
Cash dividends paid		(23,435)	(23,495)	(21,299)
Net cash provided by financing activities		285,929	379,323	281,411
Net increase in cash and cash equivalents		15,708	34,011	17,584
Cash and cash equivalents at beginning of year		109,420	75,409	57,825
Cash and cash equivalents at end of year		125,128	109,420	75,409
Supplemental disclosures of cash flow information:
Cash paid for interest		44,479	30,875	21,493
Cash paid for income taxes, net of refunds		17,171	2,022	12,599
Non cash transactions:
Transfer of loans to other real estate owned		$ 71	$ 477	$ 729

[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.