NBT Bancorp (NBTB) 10-Q 9 Nov 18 2018 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2018	Oct. 31, 2018
Document And Entity Information [Abstract]
Entity Registrant Name	NBT BANCORP INC
Entity Central Index Key	790,359
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Ex Transition Period	false
Entity Common Stock, Shares Outstanding		43,667,380
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3

Consolidated Balance Sheets (un

Consolidated Balance Sheets (unaudited) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Assets
Cash and due from banks	$ 171,525	$ 156,852
Short-term interest bearing accounts	3,108	2,812
Equity securities, at fair value	24,722	0
Securities available for sale, at fair value	1,101,074	1,255,925
Securities held to maturity (fair value $645,732 and $481,871, respectively)	659,949	484,073
Trading securities	0	11,467
Federal Reserve and Federal Home Loan Bank stock	52,421	46,706
Loans held for sale	5,035	1,134
Loans	6,887,262	6,583,639
Less allowance for loan losses	72,805	69,500
Net loans	6,814,457	6,514,139
Premises and equipment, net	78,284	81,305
Goodwill	274,769	268,043
Intangible assets, net	16,576	13,420
Bank owned life insurance	176,240	172,388
Other assets	169,124	128,548
Total assets	9,547,284	9,136,812
Liabilities
Demand (noninterest bearing)	2,373,027	2,286,892
Savings, NOW and money market	4,199,694	4,076,978
Time	868,569	806,766
Total deposits	7,441,290	7,170,636
Short-term borrowings	811,709	719,123
Long-term debt	73,751	88,869
Junior subordinated debt	101,196	101,196
Other liabilities	125,183	98,811
Total liabilities	8,553,129	8,178,635
Stockholders' equity
Preferred stock, $0.01 par value. Authorized 2,500,000 shares at September 30, 2018 and December 31, 2017	0	0
Common stock, $0.01 par value. Authorized 100,000,000 shares at September 30, 2018 and December 31, 2017; issued 49,651,493 at September 30, 2018 and December 31, 2017	497	497
Additional paid-in-capital	575,155	574,209
Retained earnings	603,921	543,713
Accumulated other comprehensive loss	(49,112)	(22,077)
Common stock in treasury, at cost, 5,990,174 and 6,108,684 shares at September 30, 2018 and December 31, 2017, respectively	(136,306)	(138,165)
Total stockholders' equity	994,155	958,177
Total liabilities and stockholders' equity	$ 9,547,284	$ 9,136,812

Consolidated Balance Sheets (_2

Consolidated Balance Sheets (unaudited) (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Assets
Securities held to maturity fair value	$ 645,732	$ 481,871
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	2,500,000	2,500,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	49,651,493	49,651,493
Common stock in treasury, at cost (in shares)	5,990,174	6,108,684

Consolidated Statements of Inco

Consolidated Statements of Income (unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Interest, fee and dividend income
Interest and fees on loans	$ 77,249	$ 68,086	$ 221,864	$ 197,399
Securities available for sale	6,659	7,278	20,588	21,505
Securities held to maturity	3,462	2,746	8,898	8,263
Other	834	737	2,381	2,010
Total interest, fee and dividend income	88,204	78,847	253,731	229,177
Interest expense
Deposits	6,157	3,648	15,167	10,658
Short-term borrowings	3,000	1,870	7,421	4,375
Long-term debt	431	589	1,359	1,794
Junior subordinated debt	1,089	810	3,030	2,308
Total interest expense	10,677	6,917	26,977	19,135
Net interest income	77,527	71,930	226,754	210,042
Provision for loan losses	6,026	7,889	22,300	22,835
Net interest income after provision for loan losses	71,501	64,041	204,454	187,207
Noninterest income
Insurance and other financial services revenue	6,172	5,536	18,502	17,927
Service charges on deposit accounts	4,503	4,261	12,721	12,399
ATM and debit card fees	5,906	5,557	16,995	16,025
Retirement plan administration fees	7,244	5,272	19,879	14,881
Trust	4,808	4,927	14,951	14,620
Bank owned life insurance	1,288	1,284	3,852	3,913
Net securities gains (losses)	412	(4)	575	(2)
Other	3,048	3,945	11,341	10,069
Total noninterest income	33,381	30,778	98,816	89,832
Noninterest expense
Salaries and employee benefits	38,394	33,674	112,687	101,410
Occupancy	5,380	5,174	17,034	16,528
Data processing and communications	4,434	4,399	13,221	12,826
Professional fees and outside services	3,580	3,107	10,408	9,748
Equipment	4,319	3,733	12,508	11,224
Office supplies and postage	1,563	1,432	4,640	4,680
FDIC expenses	1,223	1,257	3,516	3,571
Advertising	739	665	1,776	1,711
Amortization of intangible assets	1,054	993	3,064	2,999
Loan collection and other real estate owned, net	1,234	1,684	3,479	3,627
Other	4,577	4,483	13,324	13,880
Total noninterest expense	66,497	60,601	195,657	182,204
Income before income tax expense	38,385	34,218	107,613	94,835
Income tax expense	8,578	11,342	23,699	30,321
Net income	$ 29,807	$ 22,876	$ 83,914	$ 64,514
Earnings per share
Basic (in dollars per share)	$ 0.68	$ 0.52	$ 1.92	$ 1.48
Diluted (in dollars per share)	$ 0.68	$ 0.52	$ 1.91	$ 1.47

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Consolidated Statements of Comprehensive Income (unaudited) [Abstract]
Net income	$ 29,807	$ 22,876	$ 83,914	$ 64,514
Securities available for sale:
Unrealized net holding (losses) gains arising during the period, gross	(5,798)	1,355	(26,605)	4,719
Tax effect	1,449	(518)	6,651	(1,823)
Unrealized net holding (losses) gains arising during the period, net	(4,349)	837	(19,954)	2,896
Reclassification adjustment for net losses in net income, gross	0	4	0	2
Tax effect	0	(2)	0	(1)
Reclassification adjustment for net losses in net income, net	0	2	0	1
Amortization of unrealized net gains for the reclassification of available for sale securities to held to maturity, gross	168	212	533	675
Tax effect	(42)	(81)	(133)	(258)
Amortization of unrealized net gains for the reclassification of available for sale securities to held to maturity, net	126	131	400	417
Reclassification adjustment for an impairment write-down of equity security, gross	0	0	0	1,312
Tax effect	0	0	0	(501)
Reclassification adjustment for an impairment write-down of equity security, net	0	0	0	811
Total securities available for sale, net	(4,223)	970	(19,554)	4,125
Cash flow hedges:
Unrealized gains (losses) on derivatives (cash flow hedges), gross	175	91	1,647	(71)
Tax effect	(44)	(35)	(412)	27
Unrealized gains (losses) on derivatives (cash flow hedges), net	131	56	1,235	(44)
Reclassification of net unrealized (gains) on cash flow hedges to interest (income) expense, gross	(638)	(155)	(1,537)	(96)
Tax effect	159	59	384	37
Reclassification of net unrealized (gains) on cash flow hedges to interest (income) expense, net	(479)	(96)	(1,153)	(59)
Total cash flow hedges, net	(348)	(40)	82	(103)
Pension and other benefits:
Amortization of prior service cost and actuarial gains, gross	286	480	876	1,350
Tax effect	(71)	(183)	(219)	(516)
Amortization of prior service cost and actuarial gains, net	215	297	657	834
Total pension and other benefits, net	215	297	657	834
Total other comprehensive (loss) income	(4,356)	1,227	(18,815)	4,856
Comprehensive income	$ 25,451	$ 24,103	$ 65,099	$ 69,370

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity (unaudited) - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in-Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive (Loss) Income [Member]	Common Stock in Treasury [Member]	Total
Balance at Dec. 31, 2016	$ 497	$ 575,078	$ 501,761	$ (21,520)	$ (142,500)	$ 913,316
Net income	0	0	64,514	0	0	64,514
Cash dividends	0	0	(30,073)	0	0	(30,073)
Net issuance of shares to employee and other stock plans	0	(4,596)	0	0	4,026	(570)
Stock-based compensation	0	3,290	(95)	0	0	3,195
Other comprehensive (loss) income	0	0	0	4,856	0	4,856
Balance at Sep. 30, 2017	497	573,772	536,107	(16,664)	(138,474)	955,238
ASU implementation | ASU 2016-01 [Member]	0	0	2,618	(2,645)	0	(27)
ASU implementation | ASU 2018-02 [Member]	0	0	5,575	(5,575)	0	0
Balance at Dec. 31, 2017	497	574,209	543,713	(22,077)	(138,165)	958,177
Net income	0	0	83,914	0	0	83,914
Cash dividends	0	0	(31,899)	0	0	(31,899)
Net issuance of shares to employee and other stock plans	0	(2,511)	0	0	1,859	(652)
Stock-based compensation	0	3,457	0	0	0	3,457
Other comprehensive (loss) income	0	0	0	(18,815)	0	(18,815)
Balance at Sep. 30, 2018	$ 497	$ 575,155	$ 603,921	$ (49,112)	$ (136,306)	$ 994,155

Consolidated Statements of St_2

Consolidated Statements of Stockholders' Equity (unaudited) (Parenthetical) - $ / shares	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Consolidated Statements of Stockholders' Equity (unaudited) [Abstract]
Cash dividends - per share (in dollars per share)	$ 0.73	$ 0.69
Net issuance of shares to employee benefit plans and other stock plans (in shares)	118,510	271,148

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Operating activities
Net income	$ 83,914	$ 64,514
Adjustments to reconcile net income to net cash provided by operating activities
Provision for loan losses	22,300	22,835
Depreciation and amortization of premises and equipment	6,957	6,759
Net amortization on securities	3,108	3,628
Amortization of intangible assets	3,064	2,999
Excess tax (benefit) on stock-based compensation	(507)	(1,697)
Stock-based compensation expense	3,457	3,195
Bank owned life insurance income	(3,852)	(3,913)
Trading security purchases	0	(1,470)
Net unrealized losses on trading securities	0	(154)
Proceeds from sales of loans held for sale	73,239	87,095
Originations and purchases of loans held for sale	(76,959)	(87,246)
Net gains on sales of loans held for sale	(181)	(292)
Net security (gains) losses	(575)	2
Net losses (gains) on sales and write-down of other real estate owned	130	(189)
Impairment write-down of equity security	0	1,312
Net change in other assets and other liabilities	(14,313)	(810)
Net cash provided by operating activities	99,782	96,568
Investing activities
Net cash used in acquisitions	(7,884)	(4,000)
Securities available for sale:
Proceeds from maturities, calls and principal paydowns	213,732	205,327
Proceeds from sales	0	9,997
Purchases	(102,004)	(232,850)
Securities held to maturity:
Proceeds from maturities, calls and principal paydowns	73,217	86,055
Proceeds from sales	0	764
Purchases	(249,300)	(53,212)
Equity securities:
Proceeds from sales	3,318	0
Purchases	(2)	0
Other:
Net increase in loans	(323,614)	(293,346)
Proceeds from Federal Home Loan Bank stock redemption	186,869	177,803
Purchases of Federal Reserve and Federal Home Loan Bank stock	(192,584)	(175,840)
Proceeds from settlement of bank owned life insurance	0	800
Purchases of premises and equipment, net	(4,256)	(4,177)
Proceeds from the sales of other real estate owned	2,124	6,767
Net cash (used in) investing activities	(400,384)	(275,912)
Financing activities
Net increase in deposits	270,654	257,548
Net increase in short-term borrowings	92,585	248
Proceeds from issuance of long-term debt	25,000	0
Repayments of long-term debt	(40,117)	(15,174)
Proceeds from the issuance of shares to employee and other stock plans	1,140	3,012
Cash paid by employer for tax-withholdings on stock issuance	(1,792)	(3,582)
Cash dividends	(31,899)	(30,073)
Net cash provided by financing activities	315,571	211,979
Net increase in cash and cash equivalents	14,969	32,635
Cash and cash equivalents at beginning of period	159,664	149,181
Cash and cash equivalents at end of period	174,633	181,816
Cash paid during the period for:
Interest expense	26,002	19,771
Income taxes paid, net of refund	31,077	22,230
Noncash investing activities:
Loans transferred to other real estate owned	996	5,227
Acquisitions:
Fair value of assets acquired	$ 6,274	$ 3,096

Description of Business

Description of Business	9 Months Ended
	Sep. 30, 2018
Description of Business [Abstract]
Description of Business	1. Description of Business NBT Bancorp Inc. (the “Registrant” or the “Company”) is a registered financial holding company incorporated in the state of Delaware in 1986, with its principal headquarters located in Norwich, New York. The principal assets of the Registrant consist of all of the outstanding shares of common stock of its subsidiaries, including: NBT Bank, National Association (the “Bank”), NBT Financial Services, Inc. (“NBT Financial”), NBT Holdings, Inc. (“NBT Holdings”), Hathaway Agency, Inc. and CNBF Capital Trust I, NBT Statutory Trust I, NBT Statutory Trust II, Alliance Financial Capital Trust I and Alliance Financial Capital Trust II (collectively, the “Trusts”). The Company’s principal sources of revenue are the management fees and dividends it receives from the Bank, NBT Financial and NBT Holdings. The Company’s business, primarily conducted through the Bank but also through its other subsidiaries, consists of providing commercial banking, retail banking and wealth management services primarily to customers in its market area, which includes central and upstate New York, northeastern Pennsylvania, southern New Hampshire, western Massachusetts, Vermont and the southern coastal area of Maine. The Company has been, and intends to continue to be, a community-oriented financial institution offering a variety of financial services. The Company’s business philosophy is to operate as a community bank with local decision-making providing a broad array of banking and financial services to retail, commercial and municipal customers.

Basis of Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2018
Basis of Presentation [Abstract]
Basis of Presentation	2. Basis of Presentation The accompanying unaudited interim consolidated financial statements include the accounts of the Registrant and its wholly owned subsidiaries, the Bank, NBT Financial and NBT Holdings. Collectively, the Registrant and its subsidiaries are referred to herein as “the Company.” The interim data includes all adjustments, consisting only of normal recurring adjustments, necessary for a fair statement of the results for the interim periods in accordance with generally accepted accounting principles in the United States of America (“GAAP”). These unaudited interim consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in our 2017 Annual Report on Form 10-K. The results of operations for the interim periods are not necessarily indicative of the results that may be expected for the full year or any other interim period. All intercompany transactions have been eliminated in consolidation. Amounts in the prior period financial statements are reclassified whenever necessary to conform to current period presentation. The Company has evaluated subsequent events for potential recognition and/or disclosure. Refer to footnote 12, Subsequent Events, for more information.

Securities

Securities	9 Months Ended
	Sep. 30, 2018
Securities [Abstract]
Securities	3. Securities The amortized cost, estimated fair value and unrealized gains (losses) of available for sale (“AFS”) securities are as follows: (In thousands) Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value September 30, 2018 Federal agency $ 84,974 $ - $ 1,712 $ 83,262 State & municipal 36,841 13 387 36,467 Mortgage-backed: Government-sponsored enterprises 479,852 207 16,171 463,888 U.S. government agency securities 29,422 204 1,106 28,520 Collateralized mortgage obligations: Government-sponsored enterprises 461,148 222 19,860 441,510 U.S. government agency securities 49,208 115 1,896 47,427 Total AFS securities $ 1,141,445 $ 761 $ 41,132 $ 1,101,074 December 31, 2017 Federal agency $ 109,862 $ - $ 963 $ 108,899 State & municipal 42,171 62 277 41,956 Mortgage-backed: Government-sponsored enterprises 530,392 1,406 3,345 528,453 U.S. government agency securities 26,363 334 223 26,474 Collateralized mortgage obligations: Government-sponsored enterprises 496,033 254 10,114 486,173 U.S. government agency securities 50,721 165 1,065 49,821 Equity securities 10,623 3,672 146 14,149 Total AFS securities $ 1,266,165 $ 5,893 $ 16,133 $ 1,255,925 The amortized cost, estimated fair value and unrealized gains (losses) of held to maturity (“HTM”) securities are as follows: (In thousands) Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value September 30, 2018 Federal agency $ 9,995 $ - $ 46 $ 9,949 Mortgage-backed: Government-sponsored enterprises 87,743 - 4,075 83,668 U.S. government agency securities 15,241 36 69 15,208 Collateralized mortgage obligations: Government-sponsored enterprises 268,044 31 7,080 260,995 U.S. government agency securities 29,401 4 67 29,338 State & municipal 249,525 90 3,041 246,574 Total HTM securities $ 659,949 $ 161 $ 14,378 $ 645,732 December 31, 2017 Mortgage-backed: Government-sponsored enterprises $ 96,357 $ 85 $ 810 $ 95,632 U.S. government agency securities 418 57 - 475 Collateralized mortgage obligations: Government-sponsored enterprises 186,327 224 2,577 183,974 State & municipal 200,971 1,439 620 201,790 Total HTM securities $ 484,073 $ 1,805 $ 4,007 $ 481,871 AFS and HTM securities with amortized costs totaling $1.6 billion at September 30, 2018 and $1.5 billion at December 31, 2017 were pledged to secure public deposits and for other purposes required or permitted by law. Additionally, at September 30, 2018 and December 31, 2017, AFS and HTM securities with an amortized cost of $196.4 million and $256.2 million, respectively, were pledged as collateral for securities sold under repurchase agreements. The following table sets forth information with regard to investment securities with unrealized losses segregated according to the length of time the securities had been in a continuous unrealized loss position: Less than 12 months 12 months or longer Total (In thousands) Fair Value Unrealized Losses Number of Positions Fair Value Unrealized Losses Number of Positions Fair Value Unrealized Losses Number of Positions As of September 30, 2018 AFS securities: Federal agency $ 39,069 $ (916 ) 4 $ 44,193 $ (796 ) 4 $ 83,262 $ (1,712 ) 8 State & municipal 12,347 (115 ) 22 16,165 (272 ) 25 28,512 (387 ) 47 Mortgage-backed 297,802 (9,061 ) 72 178,186 (8,215 ) 48 475,988 (17,276 ) 120 Collateralized mortgage obligations 83,566 (1,816 ) 16 384,459 (19,941 ) 70 468,025 (21,757 ) 86 Total securities with unrealized losses $ 432,784 $ (11,908 ) 114 $ 623,003 $ (29,224 ) 147 $ 1,055,787 $ (41,132 ) 261 HTM securities: Federal agency $ 9,949 $ (46 ) 2 $ - $ - - $ 9,949 $ (46 ) 2 Mortgage-backed 55,712 (1,678 ) 5 42,778 (2,466 ) 4 98,490 (4,144 ) 9 Collateralized mortgage obligations 153,768 (2,195 ) 22 97,515 (4,952 ) 16 251,283 (7,147 ) 38 State & municipal 84,258 (1,276 ) 134 27,384 (1,765 ) 41 111,642 (3,041 ) 175 Total securities with unrealized losses $ 303,687 $ (5,195 ) 163 $ 167,677 $ (9,183 ) 61 $ 471,364 $ (14,378 ) 224 As of December 31, 2017 AFS securities: Federal agency $ 64,653 $ (242 ) 5 $ 44,246 $ (721 ) 4 $ 108,899 $ (963 ) 9 State & municipal 23,566 (200 ) 39 5,994 (77 ) 8 29,560 (277 ) 47 Mortgage-backed 317,630 (2,381 ) 55 58,316 (1,187 ) 24 375,946 (3,568 ) 79 Collateralized mortgage obligations 227,917 (2,658 ) 35 275,303 (8,521 ) 42 503,220 (11,179 ) 77 Equity securities - - - 2,959 (146 ) 1 2,959 (146 ) 1 Total securities with unrealized losses $ 633,766 $ (5,481 ) 134 $ 386,818 $ (10,652 ) 79 $ 1,020,584 $ (16,133 ) 213 HTM securities: Mortgage-backed $ 15,477 $ (140 ) 2 $ 33,703 $ (670 ) 2 $ 49,180 $ (810 ) 4 Collateralized mortgage obligations 118,476 (1,064 ) 17 37,614 (1,513 ) 6 156,090 (2,577 ) 23 State & municipal 22,387 (132 ) 40 15,720 (488 ) 24 38,107 (620 ) 64 Total securities with unrealized losses $ 156,340 $ (1,336 ) 59 $ 87,037 $ (2,671 ) 32 $ 243,377 $ (4,007 ) 91 Declines in the fair value of HTM securities below their amortized cost, less any current period credit loss, that are deemed to be other-than-temporary are reflected in earnings as realized losses or in other comprehensive income (“OCI”). This classification is dependent upon whether the Company intends to sell the security, or whether it is more likely than not, that the Company will be required to sell the security before recovery. The other-than-temporary impairment (“OTTI”) shall be recognized in earnings equal to the entire difference between the investment’s amortized cost basis and its fair value at the balance sheet date. If the Company does not intend to sell the security and it is not more likely than not that the Company will be required to sell the security before recovery of its amortized cost basis less any current-period credit loss, the OTTI shall be separated into (i) the amount representing the credit loss and (ii) the amount related to all other factors. The amount of the total OTTI related to the credit loss shall be recognized in earnings. The amount of the total OTTI related to other factors shall be recognized in OCI, net of applicable taxes. In estimating OTTI losses, management considers, among other things, (i) the length of time and the extent to which the fair value has been less than cost, (ii) the financial condition and near-term prospects of the issuer and (iii) the historical and implied volatility of the fair value of the security. Management has the intent to hold the securities classified as HTM until they mature, at which time it is believed the Company will receive full value for the securities. The unrealized losses on HTM debt securities are due to increases in market interest rates over yields at the time the underlying securities were purchased. When necessary, the Company has performed a discounted cash flow analysis to determine whether or not it will receive the contractual principal and interest on certain securities. The fair value is expected to recover as the bond approaches its maturity date or repricing date or if market yields for such investments declines. Management also has the intent to hold and will not be required to sell, the debt securities classified as AFS for a period of time sufficient for a recovery of cost, which may be until maturity. The unrealized losses on AFS debt securities are due to increases in market interest rates over the yields available at the time the underlying securities were purchased. When necessary, the Company has performed a discounted cash flow analysis to determine whether or not it will receive the contractual principal and interest on certain securities. For AFS debt securities, OTTI losses are recognized in earnings if the Company intends to sell the security. In other cases the Company considers the relevant factors noted above, as well as the Company’s intent and ability to retain its investment for a period of time sufficient to allow for any anticipated recovery in market value and whether evidence exists to support a realizable value equal to or greater than the cost basis. Any impairment loss on an equity security is equal to the full difference between the cost basis and the fair value of the security. As of September 30, 2018 and December 31, 2017, management believes the impairments detailed in the table above are temporary. There were no OTTI losses realized in the Company’s unaudited interim consolidated statements of income for the three and nine months ended September 30, 2018 or in the three months ended September 30, 2017. For the nine months ended September 30, 2017, a $1.3 million impairment loss on an equity investment was realized in the Company’s unaudited interim consolidated statements of income. There were no sales of HTM securities in the three and nine months ended September 30, 2018. During the three and nine months ended September 30, 2017, the Company sold HTM securities with an amortized cost of $0.8 million and an unrealized loss of $2 thousand. Due to significant deterioration in the creditworthiness of the issuers of the HTM securities, the circumstances caused the Company to change its intent to hold the HTM securities sold to maturity, which did not affect the Company’s intent to hold the remainder of the HTM portfolio to maturity. The following tables set forth information with regard to gains and losses on equity securities at September 30, 2018: (In thousands) Three months ended September 30, 2018 Nine months ended September 30, 2018 Net gains and losses recognized on equity securities $ 412 $ 575 Less: Net gains and losses recognized during the period on equity securities sold during the period 511 555 Unrealized gains and losses recognized on equity securities still held $ (99 ) $ 20 As of September 30, 2018, the carrying value of equity securities without readily determinable fair values was $4.0 million. The Company performed a qualitative assessment to determine whether the investments were impaired and identified no areas of concern as of September 30, 2018. There were no impairments, downward or upward adjustments recognized for equity securities without readily determinable fair values during the three and nine months ended September 30, 2018. The following tables set forth information with regard to contractual maturities of debt securities at September 30, 2018: (In thousands) Amortized Estimated AFS debt securities: Within one year $ 46,641 $ 46,521 From one to five years 86,348 84,188 From five to ten years 176,260 171,240 After ten years 832,196 799,125 Total AFS debt securities $ 1,141,445 $ 1,101,074 HTM debt securities: Within one year $ 89,011 $ 89,011 From one to five years 53,217 53,177 From five to ten years 215,931 209,974 After ten years 301,790 293,570 Total HTM debt securities $ 659,949 $ 645,732 Maturities of mortgage-backed, collateralized mortgage obligations and asset-backed securities are stated based on their estimated average lives. Actual maturities may differ from estimated average lives or contractual maturities because, in certain cases, borrowers have the right to call or prepay obligations with or without call or prepayment penalties. Except for U.S. Government securities, there were no holdings, when taken in the aggregate, of any single issuer that exceeded 10% of consolidated stockholders’ equity at September 30, 2018 and December 31, 2017.

Allowance for Loan Losses and C

Allowance for Loan Losses and Credit Quality of Loans	9 Months Ended
	Sep. 30, 2018
Allowance for Loan Losses and Credit Quality of Loans [Abstract]
Allowance for Loan Losses and Credit Quality of Loans	4. Allowance for Loan Losses and Credit Quality of Loans Allowance for Loan Losses The allowance for loan losses is maintained at a level estimated by management to provide adequately for probable incurred losses inherent in the current loan portfolio. The appropriateness of the allowance for loan losses is continuously monitored. It is assessed for appropriateness using a methodology designed to ensure the level of the allowance reasonably reflects the loan portfolio’s risk profile. It is evaluated to ensure that it is sufficient to absorb all reasonably estimable credit losses inherent in the current loan portfolio. To develop and document a systematic methodology for determining the allowance for loan losses, the Company has divided the loan portfolio into three segments, each with different risk characteristics and methodologies for assessing risk. Those segments are further segregated between our loans accounted for under the amortized cost method (referred to as “originated” loans) and loans acquired in a business combination (referred to as “acquired” loans). Each portfolio segment is broken down into class segments where appropriate. Class segments contain unique measurement attributes, risk characteristics and methods for monitoring and assessing risk that are necessary to develop the allowance for loan losses. Unique characteristics such as borrower type, loan type, collateral type and risk characteristics define each class segment. During the first quarter of 2018, the Company made adjustments to the class segments within the portfolios to better align risk characteristics and reflect the monitoring and assessment of risks as the portfolios continue to evolve. Agricultural and Agricultural Real Estate were consolidated with Commercial and Industrial and Commercial Real Estate, respectively. Agricultural loans are a type of Commercial loan with some specific underwriting guidelines; however, as of March 31, 2018, the portfolio had decreased to less than 3% of the Commercial portfolio and separation was no longer warranted. The Indirect class segment was further separated into Dealer Finance and Specialty Lending class segments. The growth in our Specialty Lending portfolio to 21% of Consumer Loans as of March 31, 2018 warranted evaluation of this class separately due to different risk characteristics from Dealer Finance class segments. The Direct and Home Equity class segments were consolidated into Direct to reflect common management, similar underwriting and in-market focus. The change to the class segments in the allowance methodology did not have a significant impact on the allowance for loan losses. The following table illustrates the portfolio and class segments for the loan portfolio in 2018 compared to 2017: Portfolio Class - 2018 Class - 2017 Commercial Loans Commercial and Industrial Commercial Commercial Real Estate Commercial Real Estate Business Banking Agricultural Agricultural Real Estate Business Banking Consumer Loans Dealer Finance Indirect Specialty Lending Home Equity Direct Direct Residential Real Estate Commercial Loans The Company offers a variety of Commercial loan products including Commercial and Industrial, Commercial Real Estate Commercial and Industrial (“C&I”) – Commercial Real Estate (“CRE”) – Business Banking Consumer Loans The Company offers a variety of Consumer loan products including Dealer Finance, Specialty Lending and Direct loans. Dealer Finance – Specialty Lending Direct – Residential Real Estate Residential real estate loans consist primarily of loans secured by a first or second mortgage on primary residences. We originate adjustable-rate and fixed-rate, one-to-four-family residential real estate loans for the construction, purchase or refinancing of a mortgage. These loans are collateralized by owner-occupied properties located in the Company’s market area. When market conditions are favorable, for longer term, fixed-rate residential real estate mortgages without escrow, the Company retains the servicing, but sells the right to receive principal and interest to Freddie Mac. This practice allows the Company to manage interest rate risk, liquidity risk and credit risk. Loans on one-to-four-family residential real estate are generally originated in amounts of no more than 85% of the purchase price or appraised value (whichever is lower) or have private mortgage insurance. Mortgage title insurance and hazard insurance are normally required. Construction loans have a unique risk, because they are secured by an incomplete dwelling. This risk is reduced through periodic site inspections, including one at each loan draw period. Allowance for Loan Loss Calculation For purposes of evaluating the adequacy of the allowance, the Company considers a number of significant factors that affect the collectability of the portfolio. For individually impaired loans, these include estimates of impairment, if any, which reflect the facts and circumstances that affect the likelihood of repayment of such loans as of the evaluation date. For homogeneous pools of loans, estimates of the Company’s exposure to credit loss reflect a current assessment of a number of factors, which could affect collectability. These factors include: past loss experience, size, trend, composition and nature of loans; changes in lending policies and procedures, including underwriting standards and collection, charge-offs and recoveries; trends experienced in nonperforming and delinquent loans; current economic conditions in the Company’s market; portfolio concentrations that may affect loss experienced across one or more components of the portfolio; the effect of external factors such as competition, legal and regulatory requirements; and the experience, ability and depth of lending management and staff. In addition, various regulatory agencies, as an integral component of their examination process, periodically review the Company’s allowance for loan losses. Such agencies may require the Company to make loan grade changes as well as recognize additions to the allowance based on their examinations. After a thorough consideration of the factors discussed above, any required additions or reductions to the allowance for loan losses are made periodically by charges or credits to the provision for loan losses. These charges are necessary to maintain the allowance at a level that management believes is reflective of overall level of incurred loss in the portfolio. While management uses available information to recognize losses on loans, additions and reductions of the allowance may fluctuate from one reporting period to another. These fluctuations are reflective of changes in risk associated with portfolio content or changes in management’s assessment of any or all of the determining factors discussed above. The following tables illustrate the changes in the allowance for loan losses by our portfolio segments: (In thousands) Commercial Loans Consumer Loans Residential Real Estate Total Balance as of June 30, 2018 $ 31,059 $ 36,479 $ 4,912 $ 72,450 Charge-offs (823 ) (6,818 ) (123 ) (7,764 ) Recoveries 410 1,602 81 2,093 Provision 1,086 6,044 (1,104 ) 6,026 Ending Balance as of September 30, 2018 $ 31,732 $ 37,307 $ 3,766 $ 72,805 Balance as of June 30, 2017 $ 24,428 $ 35,523 $ 6,649 $ 66,600 Charge-offs (574 ) (6,979 ) (421 ) (7,974 ) Recoveries 266 1,446 123 1,835 Provision 1,434 6,197 258 7,889 Ending Balance as of September 30, 2017 $ 25,554 $ 36,187 $ 6,609 $ 68,350 (In thousands) Commercial Loans Consumer Loans Residential Real Estate Total Balance as of December 31, 2017 $ 27,606 $ 36,830 $ 5,064 $ 69,500 Charge-offs (2,535 ) (21,947 ) (513 ) (24,995 ) Recoveries 780 4,946 274 6,000 Provision 5,881 17,478 (1,059 ) 22,300 Ending Balance as of September 30, 2018 $ 31,732 $ 37,307 $ 3,766 $ 72,805 Balance as of December 31, 2016 $ 25,444 $ 33,375 $ 6,381 $ 65,200 Charge-offs (2,991 ) (19,742 ) (1,717 ) (24,450 ) Recoveries 919 3,680 166 4,765 Provision 2,182 18,874 1,779 22,835 Ending Balance as of September 30, 2017 $ 25,554 $ 36,187 $ 6,609 $ 68,350 For acquired loans, to the extent that we experience deterioration in borrower credit quality resulting in a decrease in our expected cash flows subsequent to the acquisition of the loans, an allowance for loan losses is established based on our estimate of incurred losses at the balance sheet date. There was no allowance for loan losses for the acquired loan portfolio as of September 30, 2018 and December 31, 2017. There were no charge-offs of acquired loans for the three months ended September 30, 2018 and 2017, and approximately $0.1 million and $0.7 million during the nine months ended September 30, 2018 and 2017 of net charge-offs of acquired loans, respectively, which are included in the table above. The following tables illustrate the allowance for loan losses and the recorded investment by portfolio segments: (In thousands) Commercial Loans Consumer Loans Residential Real Estate Total As of September 30, 2018 Allowance for loan losses $ 31,732 $ 37,307 $ 3,766 $ 72,805 Allowance for loans individually evaluated for impairment 25 - - 25 Allowance for loans collectively evaluated for impairment $ 31,707 $ 37,307 $ 3,766 $ 72,780 Ending balance of loans $ 3,212,577 $ 2,301,198 $ 1,373,487 $ 6,887,262 Ending balance of originated loans individually evaluated for impairment 5,077 7,760 6,445 19,282 Ending balance of acquired loans collectively evaluated for impairment 153,808 33,994 153,073 340,875 Ending balance of originated loans collectively evaluated for impairment $ 3,053,692 $ 2,259,444 $ 1,213,969 $ 6,527,105 As of December 31, 2017 Allowance for loan losses $ 27,606 $ 36,830 $ 5,064 $ 69,500 Allowance for loans individually evaluated for impairment 57 - - 57 Allowance for loans collectively evaluated for impairment $ 27,549 $ 36,830 $ 5,064 $ 69,443 Ending balance of loans $ 3,028,269 $ 2,234,349 $ 1,321,021 $ 6,583,639 Ending balance of originated loans individually evaluated for impairment 5,876 8,432 6,830 21,138 Ending balance of acquired loans collectively evaluated for impairment 187,313 43,906 170,472 401,691 Ending balance of originated loans collectively evaluated for impairment $ 2,835,080 $ 2,182,011 $ 1,143,719 $ 6,160,810 Credit Quality of Loans For all loan classes within the Company’s loan portfolio, loans are placed on nonaccrual status when timely collection of principal and/or interest in accordance with contractual terms is in doubt. Loans are transferred to nonaccrual status generally when principal or interest payments become ninety days delinquent, unless the loan is well secured and in the process of collection or sooner when management concludes circumstances indicate that borrowers may be unable to meet contractual principal or interest payments. When a loan is transferred to a nonaccrual status, all interest previously accrued in the current period but not collected is reversed against interest income in that period. Interest accrued in a prior period and not collected is charged-off against the allowance for loan losses. If ultimate repayment of a nonaccrual loan is expected, any payments received are applied in accordance with contractual terms. If ultimate repayment of principal is not expected, any payment received on a nonaccrual loan is applied to principal until ultimate repayment becomes expected. For all loan classes within the Company’s loan portfolio, nonaccrual loans are returned to accrual status when they become current as to principal and interest and demonstrate a period of performance under the contractual terms and, in the opinion of management, are fully collectible as to principal and interest. For loans in all portfolios, the principal amount is charged off in full or in part as soon as management determines, based on available facts, that the collection of principal in full or in part is improbable. For Commercial loans, management considers specific facts and circumstances relative to individual credits in making such a determination. For Consumer and Residential Real Estate loans, management uses specific guidance and thresholds from the Federal Financial Institutions Examination Council’s Uniform Retail Credit Classification and Account Management Policy. The following tables set forth information with regard to past due and nonperforming loans by loan class: 31-60 Days Past Due Accruing 61-90 Days Past Due Accruing Greater Than 90 Days Past Due Accruing Total Past Due Accruing Nonaccrual Current Recorded As of September 30, 2018 Originated Commercial Loans: C&I $ 209 $ 41 $ - $ 250 $ 908 $ 857,782 $ 858,940 CRE 1,133 - - 1,133 3,637 1,708,369 1,713,139 Business Banking 1,318 98 - 1,416 5,754 479,520 486,690 Total Commercial Loans $ 2,660 $ 139 $ - $ 2,799 $ 10,299 $ 3,045,671 $ 3,058,769 Consumer Loans: Dealer Finance $ 14,364 $ 2,039 $ 1,252 $ 17,655 $ 2,062 $ 1,209,880 $ 1,229,597 Specialty Lending 3,037 2,155 1,544 6,736 - 514,660 521,396 Direct 3,313 949 434 4,696 2,541 508,974 516,211 Total Consumer Loans $ 20,714 $ 5,143 $ 3,230 $ 29,087 $ 4,603 $ 2,233,514 $ 2,267,204 Residential Real Estate $ 1,366 $ 219 $ 1,231 $ 2,816 $ 6,106 $ 1,211,492 $ 1,220,414 Total Originated Loans $ 24,740 $ 5,501 $ 4,461 $ 34,702 $ 21,008 $ 6,490,677 $ 6,546,387 Acquired Commercial Loans: C&I $ - $ - $ - $ - $ - $ 30,871 $ 30,871 CRE - - - - 2 87,827 87,829 Business Banking 425 - 240 665 611 33,832 35,108 Total Commercial Loans $ 425 $ - $ 240 $ 665 $ 613 $ 152,530 $ 153,808 Consumer Loans: Dealer Finance $ 4 $ - $ - $ 4 $ - $ 99 $ 103 Direct 223 14 - 237 275 33,379 33,891 Total Consumer Loans $ 227 $ 14 $ - $ 241 $ 275 $ 33,478 $ 33,994 Residential Real Estate $ 839 $ 39 $ 33 $ 911 $ 1,405 $ 150,757 $ 153,073 Total Acquired Loans $ 1,491 $ 53 $ 273 $ 1,817 $ 2,293 $ 336,765 $ 340,875 Total Loans $ 26,231 $ 5,554 $ 4,734 $ 36,519 $ 23,301 $ 6,827,442 $ 6,887,262 (In thousands) 31-60 Days Past Due Accruing 61-90 Days Past Due Accruing Greater Than 90 Days Past Due Accruing Total Past Due Accruing Nonaccrual Current Recorded Total Loans As of December 31, 2017 Originated Commercial Loans: Commercial $ - $ - $ - $ - $ 202 $ 753,577 $ 753,779 Commercial Real Estate 161 138 - 299 3,178 1,533,065 1,536,542 Agricultural 117 - - 117 1,043 34,386 35,546 Agricultural Real Estate 493 - - 493 2,736 30,905 34,134 Business Banking 1,907 597 - 2,504 5,304 473,147 480,955 Total Commercial Loans $ 2,678 $ 735 $ - $ 3,413 $ 12,463 $ 2,825,080 $ 2,840,956 Consumer Loans: Indirect $ 18,747 $ 4,033 $ 3,492 $ 26,272 $ 2,115 $ 1,642,204 $ 1,670,591 Home Equity 2,887 854 341 4,082 2,736 448,081 454,899 Direct 341 108 70 519 35 64,399 64,953 Total Consumer Loans $ 21,975 $ 4,995 $ 3,903 $ 30,873 $ 4,886 $ 2,154,684 $ 2,190,443 Residential Real Estate $ 3,730 $ 667 $ 1,262 $ 5,659 $ 5,987 $ 1,138,903 $ 1,150,549 Total Originated Loans $ 28,383 $ 6,397 $ 5,165 $ 39,945 $ 23,336 $ 6,118,667 $ 6,181,948 Acquired Commercial Loans: Commercial $ - $ - $ - $ - $ - $ 39,575 $ 39,575 Commercial Real Estate - - - - 2 106,632 106,634 Business Banking 354 - - 354 669 40,081 41,104 Total Commercial Loans $ 354 $ - $ - $ 354 $ 671 $ 186,288 $ 187,313 Consumer Loans: Indirect $ 38 $ - $ 1 $ 39 $ 22 $ 1,157 $ 1,218 Home Equity 254 34 103 391 225 39,256 39,872 Direct 6 1 1 8 23 2,785 2,816 Total Consumer Loans $ 298 $ 35 $ 105 $ 438 $ 270 $ 43,198 $ 43,906 Residential Real Estate $ 627 $ 226 $ 140 $ 993 $ 1,431 $ 168,048 $ 170,472 Total Acquired Loans $ 1,279 $ 261 $ 245 $ 1,785 $ 2,372 $ 397,534 $ 401,691 Total Loans $ 29,662 $ 6,658 $ 5,410 $ 41,730 $ 25,708 $ 6,516,201 $ 6,583,639 There were no material commitments to extend further credit to borrowers with nonperforming loans as of September 30, 2018 and December 31, 2017. Impaired Loans The methodology used to establish the allowance for loan losses on impaired loans incorporates specific allocations on loans analyzed individually. Classified loans, including all troubled debt restructured loans (“TDRs”) and nonaccrual Commercial loans that are graded Substandard, Doubtful or Loss, with outstanding balances of $750 thousand or more are evaluated for impairment through the Company’s quarterly status review process. The Company considers Commercial loans less than $750 thousand to be homogeneous loans. In determining that we will be unable to collect all principal and/or interest payments due in accordance with the contractual terms of the loan agreements, we consider factors such as payment history and changes in the financial condition of individual borrowers, local economic conditions, historical loss experience and the conditions of the various markets in which the collateral may be liquidated. For loans that are identified as impaired, impairment is measured by one of three methods: 1) the fair value of collateral less cost to sell, 2) present value of expected future cash flows or 3) the loan’s observable market price. These impaired loans are reviewed on a quarterly basis for changes in the level of impairment. Impaired amounts are charged off immediately if such amounts are determined by management to be uncollectable. Any change to the previously recognized impairment loss is recognized as a component of the provision for loan losses. The following table provides information on loans specifically evaluated for impairment: September 30, 2018 December 31, 2017 (In thousands) Recorded Investment Balance (Book) Unpaid Principal Balance (Legal) Related Allowance Recorded Investment Balance (Book) Unpaid Principal Balance (Legal) Related Allowance Originated With no related allowance recorded: Commercial Loans: C&I $ 404 $ 676 $ - $ - CRE 3,629 5,616 - - Commercial - - - 251 Commercial Real Estate - - 2,211 3,979 Agricultural - - 452 465 Agricultural Real Estate - - 2,250 2,423 Business Banking 1,019 2,099 860 1,730 Total Commercial Loans $ 5,052 $ 8,391 $ 5,773 $ 8,848 Consumer Loans: Dealer Finance $ 160 $ 254 $ - $ - Direct 7,600 9,600 - - Indirect - - 131 143 Home Equity - - 8,027 9,966 Direct - - 274 274 Total Consumer Loans $ 7,760 $ 9,854 $ 8,432 $ 10,383 Residential Real Estate $ 6,445 $ 8,721 $ 6,830 $ 8,780 Total $ 19,257 $ 26,966 $ 21,035 $ 28,011 With an allowance recorded: Commercial Loans: C&I $ 25 $ 25 $ 25 $ - $ - $ - Commercial Real Estate - - - 76 82 30 Agricultural - - - 27 27 27 Total Commercial Loans $ 25 $ 25 $ 25 $ 103 $ 109 $ 57 Total Loans $ 19,282 $ 26,991 $ 25 $ 21,138 $ 28,120 $ 57 There were no acquired impaired loans specifically evaluated for impairment as of September 30, 2018 or December 31, 2017. The following tables summarize the average recorded investments on loans specifically evaluated for impairment and the interest income recognized: For the three months ended September 30, 2018 September 30, 2017 (In thousands) Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized Originated Commercial Loans: C&I $ 433 $ - $ - $ - CRE 3,645 32 - - Commercial - - 1,000 - Commercial Real Estate - - 2,415 48 Agricultural - - 115 - Agricultural Real Estate - - 1,505 11 Business Banking 1,024 4 955 2 Total Commercial Loans $ 5,102 $ 36 $ 5,990 $ 61 Consumer Loans: Dealer Finance $ 177 $ 4 $ - $ - Direct 7,730 102 - - Indirect - - 35 1 Home Equity - - 8,159 111 Direct - - 119 2 Total Consumer Loans $ 7,907 $ 106 $ 8,313 $ 114 Residential Real Estate $ 6,519 $ 68 $ 6,633 $ 82 Total Originated Loans $ 19,528 $ 210 $ 20,936 $ 257 Total Loans $ 19,528 $ 210 $ 20,936 $ 257 For the nine months ended September 30, 2018 September 30, 2017 (In thousands) Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized Originated Commercial Loans: C&I $ 449 $ 1 $ - $ - CRE 3,999 96 - - Commercial - - 2,393 - Commercial Real Estate - - 3,906 93 Agricultural - - 147 1 Agricultural Real Estate - - 1,545 32 Business Banking 998 12 837 7 Total Commercial Loans $ 5,446 $ 109 $ 8,828 $ 133 Consumer Loans: Dealer Finance $ 187 $ 8 $ - $ - Direct 7,953 317 - - Indirect - - 22 2 Home Equity - - 8,274 331 Direct - - 119 2 Total Consumer Loans $ 8,140 $ 325 $ 8,415 $ 335 Residential Real Estate $ 6,719 $ 212 $ 6,425 $ 211 Total Originated Loans $ 20,305 $ 646 $ 23,668 $ 679 Acquired Commercial Loans: Commercial Real Estate $ - $ - $ 121 $ - Total Commercial Loans $ - $ - $ 121 $ - Total Acquired Loans $ - $ - $ 121 $ - Total Loans $ 20,305 $ 646 $ 23,789 $ 679 Credit Quality Indicators The Company has developed an internal loan grading system to evaluate and quantify the Company’s loan portfolio with respect to quality and risk. The system focuses on, among other things, financial strength of borrowers, experience and depth of borrower’s management, primary and secondary sources of repayment, payment history, nature of the business and outlook on particular industries. The internal grading system enables the Company to monitor the quality of the entire loan portfolio on a consistent basis and provide management with an early warning system, enabling recognition and response to problem loans and potential problem loans. Commercial Grading System For C&I and CRE loans, the Company uses a grading system that relies on quantifiable and measurable characteristics when available. This would include comparison of financial strength to available industry averages, comparison of transaction factors (loan terms and conditions) to loan policy and comparison of credit history to stated repayment terms and industry averages. Some grading factors are necessarily more subjective such as economic and industry factors, regulatory environment and management. C&I and CRE loans are graded Doubtful, Substandard, Special Mention and Pass. ● Doubtful A Doubtful loan has a high probability of total or substantial loss, but because of specific pending events that may strengthen the asset, its classification as a loss is deferred. Doubtful borrowers are usually in default, lack adequate liquidity or capital and lack the resources necessary to remain an operating entity. Pending events can include mergers, acquisitions, liquidations, capital injections, the perfection of liens on additional collateral, the valuation of collateral and refinancing. Generally, pending events should be resolved within a relatively short period and the ratings will be adjusted based on the new information. Nonaccrual treatment is required for Doubtful assets because of the high probability of loss. ● Substandard Substandard loans have a high probability of payment default or they have other well-defined weaknesses. They require more intensive supervision by bank management. Substandard loans are generally characterized by current or expected unprofitable operations, inadequate debt service coverage, inadequate liquidity or marginal capitalization. Repayment may depend on collateral or other credit risk mitigants. For some Substandard loans, the likelihood of full collection of interest and principal may be in doubt and those loans should be placed on nonaccrual. Although Substandard assets in the aggregate will have a distinct potential for loss, an individual asset’s loss potential does not have to be distinct for the asset to be rated Substandard. ● Special Mention Special Mention loans have potential weaknesses that may, if not checked or corrected, weaken the asset or inadequately protect the Company’s position at some future date. These loans pose elevated risk, but their weakness does not yet justify a Substandard classification. Borrowers may be experiencing adverse operating trends (i.e., declining revenues or margins) or may be struggling with an ill-proportioned balance sheet (i.e., increasing inventory without an increase in sales, high leverage, tight liquidity). Adverse economic or market conditions, such as interest rate increases or the entry of a new competitor, may also support a Special Mention rating. Although a Special Mention loan has a higher probability of default than a Pass asset, its default is not imminent. ● Pass Loans graded as Pass encompass all loans not graded as Doubtful, Substandard or Special Mention. Pass loans are in compliance with loan covenants and payments are generally made as agreed. Pass loans range from superior quality to fair quality. Business Banking Grading System Business Banking loans are graded as either Classified or Non-classified: ● Classified Classified loans are inadequately protected by the current worth and paying capacity of the obligor or, if applicable, the collateral pledged. These loans have a well-defined weakness or weaknesses, that jeopardize the liquidation of the debt or in some cases make collection or liquidation in full, on the basis of currently existing facts, conditions and values, highly questionable and improbable. They are characterized by the distinct possibility that the Company will sustain some loss if the deficiencies are not corrected. Classified loans have a high probability of payment default or a high probability of total or substantial loss. These loans require more intensive supervision by management and are generally characterized by current or expected unprofitable operations, inadequate debt service coverage, inadequate liquidity or marginal capitalization. Repayment may depend on collateral or other credit risk mitigants. When the likelihood of full collection of interest and principal may be in doubt, Classified loans are considered to have a nonaccrual status. In some cases, Classified loans are considered uncollectable and of such little value that their continuance as assets is not warranted. ● Non-classified Loans graded as Non-classified encompass all loans not graded as Classified. Non-classified loans are in compliance with loan covenants and payments are generally made as agreed. Consumer and Residential Real Estate Grading System Consumer and Residential Real Estate loans are graded as either Nonperforming or Performing. ● Nonperforming Nonperforming loans are loans that are 1) over 90 days past due and interest is still accruing or 2) on nonaccrual status. ● Performing All loans not meeting any of these criteria are considered Performing. The following tables illustrate the Company’s credit quality by loan class: (In thousands) As of September 30, 2018 Originated Commercial Credit Exposure By Internally Assigned Grade: C&I CRE Total Pass $ 805,333 $ 1,660,900 $ 2,466,233 Special Mention 33,557 16,762 50,319 Substandard 20,050 35,477 55,527 Total $ 858,940 $ 1,713,139 $ 2,572,079 Business Banking Credit Exposure By Internally Assigned Grade: Business Banking Total Non-classified $ 474,252 $ 474,252 Classified 12,438 12,438 Total $ 486,690 $ 486,690 Consumer Credit Exposure By Payment Activity: Dealer Finance Specialty Lending Direct Total Performing $ 1,226,283 $ 519,852 $ 513,236 $ 2,259,371 Nonperforming 3,314 1,544 2,975 7,833 Total $ 1,229,597 $ 521,396 $ 516,211 $ 2,267,204 Residential Real Estate Credit Exposure By Payment Activity: Residential Real Estate Total Performing $ 1,213,077 $ 1,213,077 Nonperforming 7,337 7,337 Total $ 1,220,414 $ 1,220,414 Acquired Commercial Credit Exposure By Internally Assigned Grade: C&I CRE Total Pass $ 27,046 $ 87,091 $ 114,137 Special Mention 3,825 93 3,918 Substandard - 645 645 Total $ 30,871 $ 87,829 $ 118,700 Business Banking Credit Exposure By Internally Assigned Grade: Business Banking Total Non-classified $ 32,098 $ 32,098 Classified 3,010 3,010 Total $ 35,108 $ 35,108 Consumer Credit Exposure By Payment Activity: Dealer Finance Direct Total Performing $ 103 $ 33,616 $ 33,719 Nonperforming - 275 275 Total $ 103 $ 33,891 $ 33,994 Residential Real Estate Credit Exposure By Payment Activity: Residential Real Estate Total Performing $ 151,635 $ 151,635 Nonperforming 1,438 1,438 Total $ 153,073 $ 153,073 (In thousands) As of December 31, 2017 Originated Commercial Credit Exposure By Internally Assigned Grade: Commercial Commercial Real Estate Agricultural Agricultural Real Estate Total Pass $ 708,567 $ 1,481,926 $ 31,142 $ 23,381 $ 2,245,016 Special Mention 30,337 28,264 2,294 2,441 63,336 Substandard 14,875 26,352 2,110 8,312 51,649 Total $ 753,779 $ 1,536,542 $ 35,546 $ 34,134 $ 2,360,001 Business Banking Credit Exposure By Internally Assigned Grade: Business Total Non-classified $ 468,898 $ 468,898 Classified 12,057 12,057 Total $ 480,955 $ 480,955 Consumer Credit Exposure By Payment Activity: Indirect Home Equity Direct Total Performing $ 1,664,984 $ 451,822 $ 64,848 $ 2,181,654 Nonperforming 5,607 3,077 105 8,789 Total $ 1,670,591 $ 454,899 $ 64,953 $ 2,190,443 Residential Real Estate Credit Exposure By Payment Activity: Residential Real Estate Total Performing $ 1,143,300 $ 1,143,300 Nonperforming 7,249 7,249 Total $ 1,150,549 $ 1,150,549 Acquired Commercial Credit Exposure By Internally Assigned Grade: Commercial Commercial Real Estate Total Pass $ 37,825 $ 103,248 $ 141,073 Special Mention 425 498 923 Substandard 1,325 2,888 4,213 Total $ 39,575 $ 106,634 $ 146,209 Business Banking Credit Exposure By Internally Assigned Grade: Business Banking Total Non-classified $ 38,236 $ 38,236 Classified 2,868 2,868 Total $ 41,104 $ 41,104 Consumer Credit Exposure By Payment Activity: Indirect Home Equity Direct Total Performing $ 1,195 $ 39,544 $ 2,792 $ 43,531 Nonperforming 23 328 24 375 Total $ 1,218 $ 39,872 $ 2,816 $ 43,906 Residential Real Estate Credit Exposure By Payment Activity: Residential Real Estate Total Performing $ 168,901 $ 168,901 Nonperforming 1,571 1,571 Total $ 170,472 $ 170,472 Troubled Debt Restructured Loans When the Company modifies a loan in a troubled debt restructuring, such modifications include one or a combination of the following: an extension of the maturity date at a stated rate of interest lower than the current market rate for new debt with similar risk; temporary reduction in the interest rate or change in scheduled payment amount. Residential Real Estate and Consumer TDRs occurring during 2018 and 2017 were due to the reduction in the interest rate or extension of the term. Commercial TDRs during 2018 and 2017 were both a reduction of the interest rate and change in terms. When the Company modifies a loan in a troubled debt restructuring, management measures for impairment, if any, based on the present value of the expected future cash flows, discounted at the contractual interest rate of the original loan agreement, except when the sole (remaining) source of repayment for the loan is the operation or liquidation of the collateral. In these cases, management uses the current fair value of the collateral, less selling costs. If management determines that the value of the modified loan is less than the recorded investment in the loan an impairment charge would be recognized. The following tables illustrate the recorded investment and number of modifications for modified loans, including the recorded investment in the loans prior to a modification and the recorded investment in the loans after restructuring: Three months ended September 30, 2018 (Dollars in thousands) Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Consumer Loans: Dealer Finance 8 $ 90 $ 89 Total Consumer Loans 8 $ 90 $ 89 Total Troubled Debt Restructurings 8 $ 90 $ 89 Three months ended September 30, 2017 (Dollars in thousands) Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Consumer Loans: Indirect 1 $ 7 $ 7 Home Equity 4 189 222 Total Consumer Loans 5 $ 196 $ 229 Residential Real Estate 1 $ 518 $ 518 Total Troubled Debt Restructurings 6 $ 714 $ 747 Nine months ended September 30, 2018 (Dollars in thousands) Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Commercial Loans: Business Banking 3 $ 369 $ 371 Total Commercial Loans 3 $ 369 $ 371 Consumer Loans: Dealer Finance 15 $ 185 $ 183 Direct 2 41 41 Total Consumer Loans 17 $ 226 $ 224 Residential Real Estate 5 $ 323 $ 323 Total Troubled Debt Restructurings 25 $ 918 $ 918 Nine months ended September 30, 2017 (Dollars in thousands) Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Commercial Loans: Commercial 1 $ 3,300 $ 3,239 Business Banking 1 337 333 Total Commercial Loans 2 $ 3,637 $ 3,572 Consumer Loans: Indirect 4 $ 39 $ 37 Home Equity 8 373 414 Direct 1 120 120 Total Consumer Loans 13 $ 532 $ 571 Residential Real Estate 8 $ 1,066 $ 1,068 Total Troubled Debt Restructurings 23 $ 5,235 $ 5,211 The following tables illustrate the recorded investment and number of modifications for TDRs where a concessi

Defined Benefit Post-Retirement

Defined Benefit Post-Retirement Plans	9 Months Ended
	Sep. 30, 2018
Defined Benefit Post-Retirement Plans [Abstract]
Defined Benefit Post-Retirement Plans	5. Defined Benefit Post-Retirement Plans The Company has a qualified, noncontributory, defined benefit pension plan (“the Plan”) covering substantially all of its employees at September 30, 2018. Benefits paid from the plan are based on age, years of service, compensation, social security benefits and are determined in accordance with defined formulas. The Company’s policy is to fund the Plan in accordance with Employee Retirement Income Security Act of 1974 standards. Assets of the Plan are invested in publicly traded stocks and mutual funds. In addition to the Plan, the Company also provides supplemental employee retirement plans to certain current and former executives. The Company also assumed supplemental retirement plans for certain current and former executives of Alliance Financial Corporation (“Alliance”) when the Company acquired Alliance. These supplemental employee retirement plans and the Plan are collectively referred to herein as “Pension Benefits.” In addition, the Company provides certain health care benefits for retired employees. Benefits are accrued over the employees’ active service period. Only employees that were employed by the Company on or before January 1, 2000 are eligible to receive post-retirement health care benefits. In addition, the Company assumed post-retirement medical life insurance benefits for certain Alliance employees, retirees and their spouses, if applicable, in the Alliance acquisition. These post-retirement benefits are referred to herein as “Other Benefits.” The Company made no voluntary contributions to the pension and other benefits plans during the three and nine months ended September 30, 2018 and 2017. The components of expense for Pension Benefits and Other Benefits are set forth below: Pension Benefits Other Benefits Three months ended September 30, Three months ended September 30, (In thousands) 2018 2017 2018 2017 Components of net periodic (benefit) cost Service cost $ 415 $ 329 $ 3 $ 3 Interest cost 912 1,043 82 88 Expected return on plan assets (2,119 ) (1,976 ) - - Net amortization 242 454 44 26 Total net periodic (benefit) cost $ (550 ) $ (150 ) $ 129 $ 117 Pension Benefits Other Benefits Nine months ended September 30, Nine months ended September 30, (In thousands) 2018 2017 2018 2017 Components of net periodic (benefit) cost Service cost $ 1,256 $ 1,133 $ 8 $ 9 Interest cost 2,752 3,127 245 259 Expected return on plan assets (6,364 ) (5,946 ) - - Net amortization 745 1,284 131 66 Total net periodic (benefit) cost $ (1,611 ) $ (402 ) $ 384 $ 334 The service cost component of the net periodic (benefit) cost is included in Salaries and Employee Benefits and the interest cost, expected return on plan assets and net amortization components are including in Other Noninterest Expense on the unaudited interim consolidated statements of income.

Earnings Per Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Earnings Per Share	6. Earnings Per Share Basic earnings per share (“EPS”) excludes dilution and is computed by dividing income available to common stockholders by the weighted average number of common shares outstanding for the period. Diluted EPS reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock or resulted in the issuance of common stock that then shared in the earnings of the entity (such as the Company’s dilutive stock options and restricted stock units). The following is a reconciliation of basic and diluted EPS for the periods presented in the unaudited interim consolidated statements of income: Three months ended September 30, (In thousands, except per share data) 2018 2017 Basic EPS: Weighted average common shares outstanding 43,714 43,595 Net income available to common stockholders $ 29,807 $ 22,876 Basic EPS $ 0.68 $ 0.52 Diluted EPS: Weighted average common shares outstanding 43,714 43,595 Dilutive effect of common stock options and restricted stock 337 320 Weighted average common shares and common share equivalents 44,051 43,915 Net income available to common stockholders $ 29,807 $ 22,876 Diluted EPS $ 0.68 $ 0.52 Nine months ended September 30, (In thousands, except per share data) 2018 2017 Basic EPS: Weighted average common shares outstanding 43,692 43,563 Net income available to common stockholders $ 83,914 $ 64,514 Basic EPS $ 1.92 $ 1.48 Diluted EPS: Weighted average common shares outstanding 43,692 43,563 Dilutive effect of common stock options and restricted stock 317 329 Weighted average common shares and common share equivalents 44,009 43,892 Net income available to common stockholders $ 83,914 $ 64,514 Diluted EPS $ 1.91 $ 1.47 There were 1,500 and 3,250 stock options for the quarters ended September 30, 2018 and September 30, 2017, respectively that were not considered in the calculation of diluted EPS since the stock options’ exercise price was greater than the average market price during these periods. There were 1,500 and 3,014 stock options for the nine months ended September 30, 2018 and September 30, 2017, respectively, that were not considered in the calculation of diluted EPS since the stock options’ exercise price was greater than the average market price during these periods.

Reclassification Adjustments Ou

Reclassification Adjustments Out of Other Comprehensive Income (Loss)	9 Months Ended
	Sep. 30, 2018
Reclassification Adjustments Out of Other Comprehensive Income (Loss) [Abstract]
Reclassification Adjustments Out of Other Comprehensive Income (Loss)	7. Reclassification Adjustments Out of Other Comprehensive Income (Loss) The following table summarizes the reclassification adjustments out of accumulated other comprehensive income (loss) (“AOCI”): Detail About AOCI Components Amount Reclassified From AOCI Affected Line Item in the Consolidated Statement of Comprehensive Income (Loss) Three months ended (In thousands) September 30, 2018 September 30, 2017 AFS securities: Losses on AFS securities $ - $ 4 Net securities losses Amortization of unrealized gains related to securities transfer 168 212 Interest income Tax effect $ (42 ) $ (83 ) Income tax (expense) benefit Net of tax $ 126 $ 133 Cash flow hedges: Net unrealized (gains) on cash flow hedges reclassified to interest (income) $ (638 ) $ (155 ) Interest income Tax effect $ 159 $ 59 Income tax (expense) benefit Net of tax $ (479 ) $ (96 ) Pension and other benefits: Amortization of net losses $ 263 $ 481 Other noninterest expense Amortization of prior service costs 23 (1 ) Other noninterest expense Tax effect $ (71 ) $ (183 ) Income tax (expense) benefit Net of tax $ 215 $ 297 Total reclassifications during the period, net of tax $ (138 ) $ 334 Detail About AOCI Components Amount Reclassified From AOCI Affected Line item in the Consolidated Statement of Comprehensive Income (Loss) Nine months ended (In thousands) September 30, September 30, 2017 AFS securities: Losses on AFS securities $ - $ 2 Net securities losses Amortization of unrealized gains related to securities transfer 533 675 Interest income Impairment write-down of equity security - 1,312 Other noninterest income Tax effect $ (133 ) $ (760 ) Income tax (expense) benefit Net of tax $ 400 $ 1,229 Cash flow hedges: Net unrealized (gains) on cash flow hedges reclassified to interest (income) $ (1,537 ) $ (96 ) Interest income Tax effect $ 384 $ 37 Income tax (expense) benefit Net of tax $ (1,153 ) $ (59 ) Pension and other benefits: Amortization of net losses $ 809 $ 1,351 Other noninterest expense Amortization of prior service costs 67 (1 ) Other noninterest expense Tax effect $ (219 ) $ (516 ) Income tax (expense) benefit Net of tax $ 657 $ 834 Total reclassifications during the period, net of tax $ (96 ) $ 2,004

Fair Value Measurements and Fai

Fair Value Measurements and Fair Value of Financial Instruments	9 Months Ended
	Sep. 30, 2018
Fair Value Measurements and Fair Value of Financial Instruments [Abstract]
Fair Value Measurements and Fair Value of Financial Instruments	8. Fair Value Measurements and Fair Value of Financial Instruments GAAP states that fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. Fair value measurements are not adjusted for transaction costs. A fair value hierarchy exists within GAAP that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are described below: Level 1 - Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; Level 2 - Quoted prices for similar assets or liabilities in active markets, quoted prices in markets that are not active or inputs that are observable, either directly or indirectly, for substantially the full term of the asset or liability; Level 3 - Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity). A financial instrument’s level within the fair value hierarchy is based on the lowest level of input that is significant to the fair value measurement. The types of instruments valued based on quoted market prices in active markets include most U.S. government and agency securities, many other sovereign government obligations, liquid mortgage products, active listed equities and most money market securities. Such instruments are generally classified within Level 1 or Level 2 of the fair value hierarchy. The Company does not adjust the quoted prices for such instruments. The types of instruments valued based on quoted prices in markets that are not active, broker or dealer quotations or alternative pricing sources with reasonable levels of price transparency include most investment-grade and high-yield corporate bonds, less liquid mortgage products, less liquid agency securities, less liquid listed equities, state, municipal and provincial obligations and certain physical commodities. Such instruments are generally classified within Level 2 of the fair value hierarchy. Certain common equity securities are reported at fair value utilizing Level 1 inputs (exchange quoted prices). Other investment securities are reported at fair value utilizing Level 1 and Level 2 inputs. The prices for Level 2 instruments are obtained through an independent pricing service or dealer market participants with whom the Company has historically transacted both purchases and sales of investment securities. Prices obtained from these sources include prices derived from market quotations and matrix pricing. The fair value measurements consider observable data that may include dealer quotes, market spreads, cash flows, the U.S. Treasury yield curve, live trading levels, trade execution data, market consensus prepayment speeds, credit information and the bond’s terms and conditions, among other things. Management reviews the methodologies used in pricing the securities by its third party providers. Level 3 is for positions that are not traded in active markets or are subject to transfer restrictions, valuations are adjusted to reflect illiquidity and/or non-transferability and such adjustments are generally based on available market evidence. In the absence of such evidence, management’s best estimate will be used. Management’s best estimate consists of both internal and external support on certain Level 3 investments. Subsequent to inception, management only changes Level 3 inputs and assumptions when corroborated by evidence such as transactions in similar instruments, completed or pending third-party transactions in the underlying investment or comparable entities, subsequent rounds of financing, recapitalizations and other transactions across the capital structure, offerings in the equity or debt markets and changes in financial ratios or cash flows. For the three and nine months ended September 30, 2018, the Company made no transfers of assets from Level 1 to Level 2. For the three months ended September 30, 2018, the Company made no transfers of assets from Level 2 to Level 1. For the nine months ended September 30, 2018, the Company made a $4.0 million transfer from Level 2 to Level 1. For the year ended December 31, 2017, the Company made no transfer of assets between the levels of the fair value hierarchy. The following tables set forth the Company’s financial assets and liabilities measured on a recurring basis that were accounted for at fair value. Assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement: (In thousands) Level 1 Level 2 Level 3 September 30, 2018 Assets: AFS securities Federal Agency $ - $ 83,262 $ - $ 83,262 State & municipal - 36,467 - 36,467 Mortgage-backed - 492,408 - 492,408 Collateralized mortgage obligations - 488,937 - 488,937 Total AFS securities $ - $ 1,101,074 $ - $ 1,101,074 Equity securities 20,722 4,000 - 24,722 Derivatives - 23,682 - 23,682 Total $ 20,722 $ 1,128,756 $ - $ 1,149,478 Liabilities: Derivatives $ - $ 20,054 $ - $ 20,054 Total $ - $ 20,054 $ - $ 20,054 (In thousands) Level 1 Level 2 Level 3 December 31, 2017 Assets: AFS securities Federal Agency $ - $ 108,899 $ - $ 108,899 State & municipal - 41,956 - 41,956 Mortgage-backed - 554,927 - 554,927 Collateralized mortgage obligations - 535,994 - 535,994 Other securities 5,845 8,304 - 14,149 Total AFS securities $ 5,845 $ 1,250,080 $ - $ 1,255,925 Trading securities 11,467 - - 11,467 Derivatives - 3,732 - 3,732 Total $ 17,312 $ 1,253,812 $ - $ 1,271,124 Liabilities: Derivatives $ - $ 324 $ - $ 324 Total $ - $ 324 $ - $ 324 GAAP requires disclosure of assets and liabilities measured and recorded at fair value on a non-recurring basis such as goodwill, loans held for sale, other real estate owned, collateral-dependent impaired loans, mortgage servicing rights and HTM securities. The only non-recurring fair value measurements recorded during the three and nine month periods ended September 30, 2018 and the year ended December 31, 2017 were related to impaired loans, write-down of other real estate owned and impairments of goodwill and intangible assets. The Company uses the fair value of underlying collateral, less costs to sell, to estimate the specific reserves for collateral dependent impaired loans. The appraisals may be adjusted by management for qualitative factors such as economic conditions and estimated liquidation expenses ranging from 10% to 35%. Based on the valuation techniques used, the fair value measurements for collateral dependent impaired loans are classified as Level 3. As of September 30, 2018 and December 31, 2017, the Company had collateral dependent loans with a carrying value of $25 thousand and $0.1 million, respectively, which had specific reserves including in the allowance for loan losses of $25 thousand and $0.1 million, respectively. Interest Rate Swaps The Company enters into interest rate swaps to facilitate customer transactions and meet their financing needs. These swaps are considered derivatives, but are not designated in hedging relationships. These instruments have interest rate and credit risk associated with them. To mitigate the interest rate risk, the Company enters into offsetting interest rate swaps with counterparties. The counterparty swaps are also considered derivatives and are also not designated in hedging relationships. Interest rate swaps are recorded within other assets or other liabilities on the unaudited interim consolidated balance sheet at their estimated fair value. Changes to the fair value of assets and liabilities arising from these derivatives are included, net, in other operating income in the unaudited interim consolidated statement of income. At September 30, 2018 the notional amount of these customer derivative agreements and the offsetting derivative counterparty positions each totaled $630.2 million and the fair values included in other assets and other liabilities on the unaudited interim consolidated balance sheet applicable to these agreements amounted to $20.0 million. At December 31, 2017, the notional amount of these customer derivative agreements and the offsetting derivative counterparty positions each totaled $481.2 million and the fair values included in other assets and other liabilities on the unaudited interim consolidated balance sheet applicable to these agreements amounted to $0.2 million. The Company has entered into interest rate swaps to modify the interest rate characteristics of certain short-term FHLB advances from variable rate to fixed rate in order to reduce the impact of changes in future cash flows due to market interest rate changes. These agreements are designated as cash flow hedges. The notional amount of these interest rate derivative agreements total $225.0 million at September 30, 2018 and $250.0 million at December 31, 2017. Fair values included in other assets on the unaudited interim consolidated balance sheet applicable to these agreements amounted to $3.6 million at September 30, 2018 and $3.5 million at December 31, 2017. For derivatives designated and that qualify as cash flow hedges of interest rate risk, the gain or loss on the derivative is recorded in AOCI and subsequently reclassified into interest expense in the same period during which the hedge transaction affects earnings. Amounts reported in AOCI related to derivatives will be reclassified to interest expense as interest payments are made on the Company’s short-term rate borrowings. The change in net unrealized gains (losses) on cash flow hedges reflects a reclassification of $0.6 million of net unrealized gains and $0.2 million of net unrealized (losses) for AOCI to interest expense during the three months ended September 30, 2018 and 2017, respectively. The change in net unrealized gains (losses) on cash flow hedges reflects a reclassification of $1.5 million and $0.1 million of net unrealized gains from AOCI to interest expense during the nine months ended September 30, 2018 and 2017, respectively. During the next twelve months, the Company estimates that an additional $3.0 million will be reclassified from AOCI as a reduction to interest expense. The following table sets forth information with regard to estimated fair values of financial instruments. This table excludes financial instruments for which the carrying amount approximates fair value. Financial instruments for which the fair value approximates carrying value include cash and cash equivalents, AFS securities, equity securities, trading securities, accrued interest receivable, non-maturity deposits, short-term borrowings, accrued interest payable and interest rate swaps. September 30, 2018 December 31, 2017 (In thousands) Fair Value Carrying Amount Estimated Fair Value Carrying Amount Estimated Fair Value Financial assets: HTM securities 2 $ 659,949 $ 645,732 $ 484,073 $ 481,871 Net loans 3 6,819,492 6,762,901 6,515,273 6,651,931 Financial liabilities: Time deposits 2 $ 868,569 $ 860,791 $ 806,766 $ 801,294 Long-term debt 2 73,751 72,152 88,869 88,346 Junior subordinated debt 2 101,196 102,979 101,196 104,593 Fair value estimates are made at a specific point in time, based on relevant market information and information about the financial instrument. These estimates do not reflect any premium or discount that could result from offering for sale at one time the Company’s entire holdings of a particular financial instrument. Because no market exists for a significant portion of the Company’s financial instruments, fair value estimates are based on judgments regarding future expected loss experience, current economic conditions, risk characteristics of various financial instruments and other factors. These estimates are subjective in nature and involve uncertainties and matters of significant judgment and therefore cannot be determined with precision. Changes in assumptions could significantly affect the estimates. Fair value estimates are based on existing on and off-balance sheet financial instruments without attempting to estimate the value of anticipated future business and the value of assets and liabilities that are not considered financial instruments. For example, the Company has a substantial trust and investment management operation that contributes net fee income annually. The trust and investment management operation is not considered a financial instrument and its value has not been incorporated into the fair value estimates. Other significant assets and liabilities include the benefits resulting from the low-cost funding of deposit liabilities as compared to the cost of borrowing funds in the market and premises and equipment. In addition, the tax ramifications related to the realization of the unrealized gains and losses can have a significant effect on fair value estimates and have not been considered in the estimate of fair value. HTM Securities The fair value of the Company’s investment HTM securities is primarily measured using information from a third party pricing service. The fair value measurements consider observable data that may include dealer quotes, market spreads, cash flows, the U.S. Treasury yield curve, live trading levels, trade execution data, market consensus prepayment speeds, credit information and the bond’s terms and conditions, among other things. Net Loans The fair value of the Company’s loans was estimated by discounting the expected future cash flows using the current interest rates at which similar loans would be made for the same remaining maturities, in accordance with the exit price notion as defined by Financial Accounting Standards Board (“FASB”) Accounting Standard Codification (“ASC”) 820, Fair Value Measurement Financial Instruments - Overall (Subtopic 825-10) - Recognition and Measurement of Financial Assets and Financial Liabilities Time Deposits The fair value of time deposits was estimated using a discounted cash flow approach that applies prevailing market interest rates for similar maturity instruments. The fair values of the Company’s time deposit liabilities do not take into consideration the value of the Company’s long-term relationships with depositors, which may have significant value. Long-Term Debt The fair value of long-term debt was estimated using a discounted cash flow approach that applies prevailing market interest rates for similar maturity instruments. Junior Subordinated Debt The fair value of junior subordinated debt has been estimated using a discounted cash flow analysis.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2018
Commitments and Contingencies [Abstract]
Commitments and Contingencies	9. Commitments and Contingencies The Company is a party to financial instruments with off-balance sheet risk in the normal course of business to meet the financing needs of its customers. These financial instruments include commitments to extend credit, unused lines of credit, standby letters of credit and certain Commercial loans sold to investors with recourse, with the sold portion having a government guarantee that is assignable back to the Company upon repurchase of the loan in the event of default. The Company’s exposure to credit loss in the event of nonperformance by the other party to the commitments to extend credit, unused lines of credit, standby letters of credit and loans sold with recourse is represented by the contractual amounts of those investments. The credit risk associated with commitments to extend credit and standby and commercial letters of credit is essentially the same as that involved with extending loans to customers and is subject to normal credit policies. Commitments to extend credit and unused lines of credit totaled $1.7 billion at September 30, 2018 and $1.6 billion at December 31, 2017. Since many loan commitments, standby letters of credit, guarantees and indemnification contracts expire without being funded in whole or in part, the contract amounts are not necessarily indicative of future cash flows. The Company does not issue any guarantee that would require liability-recognition or disclosure, other than its standby letters of credit. The Company guarantees the obligations or performance of customers by issuing standby letters of credit to third parties. These standby letters of credit are frequently issued in support of third party debt, such as corporate debt issuances, industrial revenue bonds and municipal securities. The risk involved in issuing standby letters of credit is essentially the same as the credit risk involved in extending loan facilities to customers and they are subject to the same credit origination guidelines, portfolio maintenance and management procedures in effect to monitor other credit and off-balance sheet products. Typically, these instruments have terms of five years or less and expire unused; therefore, the total amounts do not necessarily represent future cash commitments. Standby letters of credit totaled $39.5 million at September 30, 2018 and $41.1 million at December 31, 2017. As of September 30, 2018 and December 31, 2017, the fair value of standby letters of credit was not significant.

Revenue from Contracts with Cus

Revenue from Contracts with Customers	9 Months Ended
	Sep. 30, 2018
Revenue from Contracts with Customers [Abstract]
Revenue from Contracts with Customers	10. Revenue from Contracts with Customers Effective January 1, 2018, the Company adopted FASB ASU 2014-09, Revenue from Contracts with Customers (ASC Topic 606) Insurance and Other Financial Services Revenue Insurance and other financial services revenue primarily consists of commissions received on insurance and brokered investment product sales. The Company acts as an intermediary between the Company’s customer and the insurance carrier. The Company’s performance obligation is generally satisfied upon the issuance of the annuity policy. Shortly after the policy is issued, the carrier remits the commission payment to the Company, and the Company recognizes the revenue. The Company does not earn a significant amount of trailing commission fees on insurance or brokered investment product sales. The majority of the trailing commission fees are calculated based on a percentage of market value of a period end and revenue is recognized when an investment product’s market value can be determined. Service Charges on Deposit Accounts Service charges on deposit accounts consist of overdraft fees, monthly service fees, check orders and other deposit account related fees. Overdraft, monthly service, check orders and other deposit account related fees are transactional based, and therefore, the Company’s performance obligation is satisfied, and related revenue recognized, at a point in time. Payment for service charges on deposit accounts is primarily received immediately or in the following month through a direct charge to customers’ accounts. ATM and Debit Card Fees ATM fees are primarily generated when a Company cardholder uses a non-Company ATM or a non-Company cardholder uses a Company ATM. Debit card income is primarily comprised of interchange fees earned whenever the Company’s debit cards are processed through card payment networks. The Company’s performance obligations for these revenue streams are satisfied, and related revenue recognized, when the services are rendered or upon completion. Payment is typically received immediately or in the following month. Retirement Plan Administration Fees Retirement plan administration fees are primarily generated for services related to the recordkeeping, administration and plan design solutions of defined benefit, defined contribution and revenue sharing plans. Revenue is recognized in arrears for services already provided in accordance with fees established in contracts with customers or based on rates agreed to with investment trade platforms based on ending investment balances held. The Company’s performance obligation is satisfied, and related revenue recognized based on services completed or ending investment balances, for which receivables are recorded at the time of revenue recognition. Trust Trust and asset management income is primarily comprised of fees earned from the management and administration of trusts, pensions and other customer assets. The Company’s performance obligation is generally satisfied with the resulting fees recognized monthly, based upon services completed or the month-end market value of the assets under management and the applicable fee rate. Payment is generally received shortly after services are rendered or a few days after month end through a direct charge to customers’ accounts. The Company does not earn performance-based incentives. Other Other noninterest income consists of other recurring revenue streams such as account and loan fees, interest rate swap fees, safety deposit box rental fees and other miscellaneous revenue streams. These revenue streams are primarily transactional based and payment is received immediately or in the following month, and therefore, the Company’s performance obligation is satisfied, and related revenue recognized, at a point in time. The following table presents noninterest income, segregated by revenue streams in-scope and out-of-scope of ASC 606, for three and nine months ended September 30, 2018 and 2017: Three months ended September 30, Nine months ended September 30, (In thousands) 2018 2017 2018 2017 Noninterest income In-Scope of ASC 606: Insurance and other financial services revenue $ 6,172 $ 5,536 $ 18,502 $ 17,927 Service charges on deposit accounts 4,503 4,261 12,721 12,399 ATM and debit card fees 5,906 5,557 16,995 16,025 Retirement plan administration fees 7,244 5,272 19,879 14,881 Trust 4,808 4,927 14,951 14,620 Other 3,048 3,945 11,341 10,069 Total noninterest income in-scope of ASC 606 $ 31,681 $ 29,498 $ 94,389 $ 85,921 Total noninterest income out-of-scope of ASC 606 $ 1,700 $ 1,280 $ 4,427 $ 3,911 Total noninterest income $ 33,381 $ 30,778 $ 98,816 $ 89,832 Contract Balances A contract asset balance occurs when an entity performs a service for a customer before the customer pays consideration or before payment is due, which would result in contract receivables or assets, respectively. A contract liability balance is an entity’s obligation to transfer a service to a customer for which the entity has already received payment or for which payment is due from the customer. The Company’s noninterest revenue streams are largely based on transactional activity, or standard month-end revenue accruals such as asset management fees based on month-end market values. Consideration is often received immediately or shortly after the Company satisfies its performance obligation and revenue is recognized. The Company does not typically enter into long-term revenue contracts with customers, and therefore, does not experience significant contract balances. As of September 30, 2018 and December 31, 2017, the Company did not have any significant contract balances. Contract Acquisition Costs ASC 606 requires the capitalization, and subsequently amortization into expense, certain incremental costs of obtaining a contract with a customer if these costs are expected to be recovered. The incremental costs of obtaining a contract are those costs that an entity incurs to obtain a contract with a customer that it would not have incurred if the contract had not been obtained. The Company elected the practical expedient, which allows immediate expensing of contract acquisition costs when the asset that would have resulted from capitalizing these costs would have been amortized in one year or less, and did not capitalize any contract acquisition costs upon adoption of ASC 606 as of or during the three and nine months ended September 30, 2018.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	9 Months Ended
	Sep. 30, 2018
Recent Accounting Pronouncements [Abstract]
Recent Accounting Pronouncements	11. Recent Accounting Pronouncements Recently Adopted Accounting Standards Effective January 1, 2018, the Company early adopted the provisions of FASB ASU 2018-02, Income Statement – Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income Effective January 1, 2018, the Company early adopted the provisions of FASB ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities adoption did not have an impact on the consolidated financial statements and related disclosures. Effective January 1, 2018, the Company adopted the provisions of FASB ASU 2017-09, Compensation-Stock Compensation (Topic 718) Effective January 1, 2018, the Company adopted the provisions of FASB ASU 2017-07, Compensation – Retirement Benefits (Topic 715) Effective January 1, 2018, the Company adopted the provisions of FASB ASU 2017-05, Other Income – Gains and Losses from the Derecognition of Nonfinancial Assets (Subtopic 610-20) Effective January 1, 2018, the Company adopted the provisions of FASB ASU 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business, adoption did not have an impact on the consolidated financial statements and related disclosures. Effective January 1, 2018, the Company adopted the provisions of FASB Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments) The amendments of ASU 2016-15 were applied on a retrospective adoption did not have an impact on the consolidated financial statements and related disclosures. Effective January 1, 2018, the Company adopted the provisions of FASB Financial Instruments - Overall (Subtopic 825-10) – Recognition and Measurement of Financial Assets and Financial Liabilities Effective January 1, 2018, the Company adopted the provisions of FASB ipal versus Agent Considerations (Reporting Revenue Gross versus Net) Identifying Performance Obligations and Licensing Narrow-Scope Improvements and Practical Expedients, Technical Corrections and Improvements to Topic 606 - Revenue from Contract with Customers Management determined that the majority of revenue earned by the Company is from revenue streams not included in the scope of this standard such as interest earned from loans, investment securities and bank owned life insurance income. For applicable revenue streams such as ATM and debit card fees, insurance, other financial services revenue, service charges on deposit accounts, retirement plan administration fees and trust fees, management reviewed the applicable contracts provisions and applied the principles in the new standard for revenue recognition. The amendments of ASU 2014-09 were applied on a modified retrospective basis. There was no cumulative effect adjustment as of January 1, 2018. The adoption of ASU 2014-09 and all related ASU updates to ASC 606 did not have a significant impact on the consolidated financial statements and related disclosures as of and for three and nine months ended September 30, 2018. Refer to footnote 10, Revenue from Contracts with Customers, for more information. Accounting Standards Issued Not Yet Adopted In August 2018, the FASB issued ASU 2018-13, Fair value Measurement (Topic 820) – Disclosure Framework – Changes to the Disclosure Requirements for Fair value Measurement. In February 2018, the FASB issued ASU 2018-03, Technical Correction and Improvement to Financial Instruments – Overall (Subtopic 825-10) In March 2017, the FASB issued ASU 2017-08, Receivables – Nonrefundable Fees and Other Costs (Subtopic 310-20) In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) Leases (Topic 842): Land Easement Practical Expedient for Transition to Topic 842 Codification Improvements to Topic 842, Leases Targeted Improvements

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2018
Subsequent Events [Abstract]
Subsequent Events	12. Subsequent Events Subsequent to September 30, 2018, the Company received a letter ruling from the Internal Revenue Service National Office approving a change in tax accounting method, which resulted in a tax benefit of $4.7 million recorded in the fourth quarter of 2018.

Description of Business (Polici

Description of Business (Policies)	9 Months Ended
	Sep. 30, 2018
Description of Business [Abstract]
Nature of Operations	NBT Bancorp Inc. (the “Registrant” or the “Company”) is a registered financial holding company incorporated in the state of Delaware in 1986, with its principal headquarters located in Norwich, New York. The principal assets of the Registrant consist of all of the outstanding shares of common stock of its subsidiaries, including: NBT Bank, National Association (the “Bank”), NBT Financial Services, Inc. (“NBT Financial”), NBT Holdings, Inc. (“NBT Holdings”), Hathaway Agency, Inc. and CNBF Capital Trust I, NBT Statutory Trust I, NBT Statutory Trust II, Alliance Financial Capital Trust I and Alliance Financial Capital Trust II (collectively, the “Trusts”). The Company’s principal sources of revenue are the management fees and dividends it receives from the Bank, NBT Financial and NBT Holdings. The Company’s business, primarily conducted through the Bank but also through its other subsidiaries, consists of providing commercial banking, retail banking and wealth management services primarily to customers in its market area, which includes central and upstate New York, northeastern Pennsylvania, southern New Hampshire, western Massachusetts, Vermont and the southern coastal area of Maine. The Company has been, and intends to continue to be, a community-oriented financial institution offering a variety of financial services. The Company’s business philosophy is to operate as a community bank with local decision-making providing a broad array of banking and financial services to retail, commercial and municipal customers.

Basis of Presentation (Policies

Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2018
Basis of Presentation [Abstract]
Basis of Presentation	The accompanying unaudited interim consolidated financial statements include the accounts of the Registrant and its wholly owned subsidiaries, the Bank, NBT Financial and NBT Holdings. Collectively, the Registrant and its subsidiaries are referred to herein as “the Company.” The interim data includes all adjustments, consisting only of normal recurring adjustments, necessary for a fair statement of the results for the interim periods in accordance with generally accepted accounting principles in the United States of America (“GAAP”). These unaudited interim consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in our 2017 Annual Report on Form 10-K. The results of operations for the interim periods are not necessarily indicative of the results that may be expected for the full year or any other interim period. All intercompany transactions have been eliminated in consolidation. Amounts in the prior period financial statements are reclassified whenever necessary to conform to current period presentation. The Company has evaluated subsequent events for potential recognition and/or disclosure. Refer to footnote 12, Subsequent Events, for more information.

Securities (Policies)

Securities (Policies)	9 Months Ended
	Sep. 30, 2018
Securities [Abstract]
Investment, Policy	Declines in the fair value of HTM securities below their amortized cost, less any current period credit loss, that are deemed to be other-than-temporary are reflected in earnings as realized losses or in other comprehensive income (“OCI”). This classification is dependent upon whether the Company intends to sell the security, or whether it is more likely than not, that the Company will be required to sell the security before recovery. The other-than-temporary impairment (“OTTI”) shall be recognized in earnings equal to the entire difference between the investment’s amortized cost basis and its fair value at the balance sheet date. If the Company does not intend to sell the security and it is not more likely than not that the Company will be required to sell the security before recovery of its amortized cost basis less any current-period credit loss, the OTTI shall be separated into (i) the amount representing the credit loss and (ii) the amount related to all other factors. The amount of the total OTTI related to the credit loss shall be recognized in earnings. The amount of the total OTTI related to other factors shall be recognized in OCI, net of applicable taxes. In estimating OTTI losses, management considers, among other things, (i) the length of time and the extent to which the fair value has been less than cost, (ii) the financial condition and near-term prospects of the issuer and (iii) the historical and implied volatility of the fair value of the security. Management has the intent to hold the securities classified as HTM until they mature, at which time it is believed the Company will receive full value for the securities. The unrealized losses on HTM debt securities are due to increases in market interest rates over yields at the time the underlying securities were purchased. When necessary, the Company has performed a discounted cash flow analysis to determine whether or not it will receive the contractual principal and interest on certain securities. The fair value is expected to recover as the bond approaches its maturity date or repricing date or if market yields for such investments declines. Management also has the intent to hold and will not be required to sell, the debt securities classified as AFS for a period of time sufficient for a recovery of cost, which may be until maturity. The unrealized losses on AFS debt securities are due to increases in market interest rates over the yields available at the time the underlying securities were purchased. When necessary, the Company has performed a discounted cash flow analysis to determine whether or not it will receive the contractual principal and interest on certain securities. For AFS debt securities, OTTI losses are recognized in earnings if the Company intends to sell the security. In other cases the Company considers the relevant factors noted above, as well as the Company’s intent and ability to retain its investment for a period of time sufficient to allow for any anticipated recovery in market value and whether evidence exists to support a realizable value equal to or greater than the cost basis. Any impairment loss on an equity security is equal to the full difference between the cost basis and the fair value of the security. Maturities of mortgage-backed, collateralized mortgage obligations and asset-backed securities are stated based on their estimated average lives. Actual maturities may differ from estimated average lives or contractual maturities because, in certain cases, borrowers have the right to call or prepay obligations with or without call or prepayment penalties.

Allowance for Loan Losses and_2

Allowance for Loan Losses and Credit Quality of Loans (Policies)	9 Months Ended
	Sep. 30, 2018
Allowance for Loan Losses and Credit Quality of Loans [Abstract]
Portfolio and Class Segments	Portfolio Class - 2018 Class - 2017 Commercial Loans Commercial and Industrial Commercial Commercial Real Estate Commercial Real Estate Business Banking Agricultural Agricultural Real Estate Business Banking Consumer Loans Dealer Finance Indirect Specialty Lending Home Equity Direct Direct Residential Real Estate
Allowance for Loan Losses	Allowance for Loan Losses The allowance for loan losses is maintained at a level estimated by management to provide adequately for probable incurred losses inherent in the current loan portfolio. The appropriateness of the allowance for loan losses is continuously monitored. It is assessed for appropriateness using a methodology designed to ensure the level of the allowance reasonably reflects the loan portfolio’s risk profile. It is evaluated to ensure that it is sufficient to absorb all reasonably estimable credit losses inherent in the current loan portfolio. To develop and document a systematic methodology for determining the allowance for loan losses, the Company has divided the loan portfolio into three segments, each with different risk characteristics and methodologies for assessing risk. Those segments are further segregated between our loans accounted for under the amortized cost method (referred to as “originated” loans) and loans acquired in a business combination (referred to as “acquired” loans). Each portfolio segment is broken down into class segments where appropriate. Class segments contain unique measurement attributes, risk characteristics and methods for monitoring and assessing risk that are necessary to develop the allowance for loan losses. Unique characteristics such as borrower type, loan type, collateral type and risk characteristics define each class segment. During the first quarter of 2018, the Company made adjustments to the class segments within the portfolios to better align risk characteristics and reflect the monitoring and assessment of risks as the portfolios continue to evolve. Agricultural and Agricultural Real Estate were consolidated with Commercial and Industrial and Commercial Real Estate, respectively. Agricultural loans are a type of Commercial loan with some specific underwriting guidelines; however, as of March 31, 2018, the portfolio had decreased to less than 3% of the Commercial portfolio and separation was no longer warranted. The Indirect class segment was further separated into Dealer Finance and Specialty Lending class segments. The growth in our Specialty Lending portfolio to 21% of Consumer Loans as of March 31, 2018 warranted evaluation of this class separately due to different risk characteristics from Dealer Finance class segments. The Direct and Home Equity class segments were consolidated into Direct to reflect common management, similar underwriting and in-market focus. The change to the class segments in the allowance methodology did not have a significant impact on the allowance for loan losses. Commercial Loans The Company offers a variety of Commercial loan products including Commercial and Industrial, Commercial Real Estate Commercial and Industrial (“C&I”) – Commercial Real Estate (“CRE”) – Business Banking Consumer Loans The Company offers a variety of Consumer loan products including Dealer Finance, Specialty Lending and Direct loans. Dealer Finance – Specialty Lending Direct – Residential Real Estate Residential real estate loans consist primarily of loans secured by a first or second mortgage on primary residences. We originate adjustable-rate and fixed-rate, one-to-four-family residential real estate loans for the construction, purchase or refinancing of a mortgage. These loans are collateralized by owner-occupied properties located in the Company’s market area. When market conditions are favorable, for longer term, fixed-rate residential real estate mortgages without escrow, the Company retains the servicing, but sells the right to receive principal and interest to Freddie Mac. This practice allows the Company to manage interest rate risk, liquidity risk and credit risk. Loans on one-to-four-family residential real estate are generally originated in amounts of no more than 85% of the purchase price or appraised value (whichever is lower) or have private mortgage insurance. Mortgage title insurance and hazard insurance are normally required. Construction loans have a unique risk, because they are secured by an incomplete dwelling. This risk is reduced through periodic site inspections, including one at each loan draw period. Allowance for Loan Loss Calculation For purposes of evaluating the adequacy of the allowance, the Company considers a number of significant factors that affect the collectability of the portfolio. For individually impaired loans, these include estimates of impairment, if any, which reflect the facts and circumstances that affect the likelihood of repayment of such loans as of the evaluation date. For homogeneous pools of loans, estimates of the Company’s exposure to credit loss reflect a current assessment of a number of factors, which could affect collectability. These factors include: past loss experience, size, trend, composition and nature of loans; changes in lending policies and procedures, including underwriting standards and collection, charge-offs and recoveries; trends experienced in nonperforming and delinquent loans; current economic conditions in the Company’s market; portfolio concentrations that may affect loss experienced across one or more components of the portfolio; the effect of external factors such as competition, legal and regulatory requirements; and the experience, ability and depth of lending management and staff. In addition, various regulatory agencies, as an integral component of their examination process, periodically review the Company’s allowance for loan losses. Such agencies may require the Company to make loan grade changes as well as recognize additions to the allowance based on their examinations. After a thorough consideration of the factors discussed above, any required additions or reductions to the allowance for loan losses are made periodically by charges or credits to the provision for loan losses. These charges are necessary to maintain the allowance at a level that management believes is reflective of overall level of incurred loss in the portfolio. While management uses available information to recognize losses on loans, additions and reductions of the allowance may fluctuate from one reporting period to another. These fluctuations are reflective of changes in risk associated with portfolio content or changes in management’s assessment of any or all of the determining factors discussed above. For acquired loans, to the extent that we experience deterioration in borrower credit quality resulting in a decrease in our expected cash flows subsequent to the acquisition of the loans, an allowance for loan losses is established based on our estimate of incurred losses at the balance sheet date. Credit Quality of Loans For all loan classes within the Company’s loan portfolio, loans are placed on nonaccrual status when timely collection of principal and/or interest in accordance with contractual terms is in doubt. Loans are transferred to nonaccrual status generally when principal or interest payments become ninety days delinquent, unless the loan is well secured and in the process of collection or sooner when management concludes circumstances indicate that borrowers may be unable to meet contractual principal or interest payments. When a loan is transferred to a nonaccrual status, all interest previously accrued in the current period but not collected is reversed against interest income in that period. Interest accrued in a prior period and not collected is charged-off against the allowance for loan losses. If ultimate repayment of a nonaccrual loan is expected, any payments received are applied in accordance with contractual terms. If ultimate repayment of principal is not expected, any payment received on a nonaccrual loan is applied to principal until ultimate repayment becomes expected. For all loan classes within the Company’s loan portfolio, nonaccrual loans are returned to accrual status when they become current as to principal and interest and demonstrate a period of performance under the contractual terms and, in the opinion of management, are fully collectible as to principal and interest. For loans in all portfolios, the principal amount is charged off in full or in part as soon as management determines, based on available facts, that the collection of principal in full or in part is improbable. For Commercial loans, management considers specific facts and circumstances relative to individual credits in making such a determination. For Consumer and Residential Real Estate loans, management uses specific guidance and thresholds from the Federal Financial Institutions Examination Council’s Uniform Retail Credit Classification and Account Management Policy. Impaired Loans The methodology used to establish the allowance for loan losses on impaired loans incorporates specific allocations on loans analyzed individually. Classified loans, including all troubled debt restructured loans (“TDRs”) and nonaccrual Commercial loans that are graded Substandard, Doubtful or Loss, with outstanding balances of $750 thousand or more are evaluated for impairment through the Company’s quarterly status review process. The Company considers Commercial loans less than $750 thousand to be homogeneous loans. In determining that we will be unable to collect all principal and/or interest payments due in accordance with the contractual terms of the loan agreements, we consider factors such as payment history and changes in the financial condition of individual borrowers, local economic conditions, historical loss experience and the conditions of the various markets in which the collateral may be liquidated. For loans that are identified as impaired, impairment is measured by one of three methods: 1) the fair value of collateral less cost to sell, 2) present value of expected future cash flows or 3) the loan’s observable market price. These impaired loans are reviewed on a quarterly basis for changes in the level of impairment. Impaired amounts are charged off immediately if such amounts are determined by management to be uncollectable. Any change to the previously recognized impairment loss is recognized as a component of the provision for loan losses. Credit Quality Indicators The Company has developed an internal loan grading system to evaluate and quantify the Company’s loan portfolio with respect to quality and risk. The system focuses on, among other things, financial strength of borrowers, experience and depth of borrower’s management, primary and secondary sources of repayment, payment history, nature of the business and outlook on particular industries. The internal grading system enables the Company to monitor the quality of the entire loan portfolio on a consistent basis and provide management with an early warning system, enabling recognition and response to problem loans and potential problem loans. Commercial Grading System For C&I and CRE loans, the Company uses a grading system that relies on quantifiable and measurable characteristics when available. This would include comparison of financial strength to available industry averages, comparison of transaction factors (loan terms and conditions) to loan policy and comparison of credit history to stated repayment terms and industry averages. Some grading factors are necessarily more subjective such as economic and industry factors, regulatory environment and management. C&I and CRE loans are graded Doubtful, Substandard, Special Mention and Pass. ● Doubtful A Doubtful loan has a high probability of total or substantial loss, but because of specific pending events that may strengthen the asset, its classification as a loss is deferred. Doubtful borrowers are usually in default, lack adequate liquidity or capital and lack the resources necessary to remain an operating entity. Pending events can include mergers, acquisitions, liquidations, capital injections, the perfection of liens on additional collateral, the valuation of collateral and refinancing. Generally, pending events should be resolved within a relatively short period and the ratings will be adjusted based on the new information. Nonaccrual treatment is required for Doubtful assets because of the high probability of loss. ● Substandard Substandard loans have a high probability of payment default or they have other well-defined weaknesses. They require more intensive supervision by bank management. Substandard loans are generally characterized by current or expected unprofitable operations, inadequate debt service coverage, inadequate liquidity or marginal capitalization. Repayment may depend on collateral or other credit risk mitigants. For some Substandard loans, the likelihood of full collection of interest and principal may be in doubt and those loans should be placed on nonaccrual. Although Substandard assets in the aggregate will have a distinct potential for loss, an individual asset’s loss potential does not have to be distinct for the asset to be rated Substandard. ● Special Mention Special Mention loans have potential weaknesses that may, if not checked or corrected, weaken the asset or inadequately protect the Company’s position at some future date. These loans pose elevated risk, but their weakness does not yet justify a Substandard classification. Borrowers may be experiencing adverse operating trends (i.e., declining revenues or margins) or may be struggling with an ill-proportioned balance sheet (i.e., increasing inventory without an increase in sales, high leverage, tight liquidity). Adverse economic or market conditions, such as interest rate increases or the entry of a new competitor, may also support a Special Mention rating. Although a Special Mention loan has a higher probability of default than a Pass asset, its default is not imminent. ● Pass Loans graded as Pass encompass all loans not graded as Doubtful, Substandard or Special Mention. Pass loans are in compliance with loan covenants and payments are generally made as agreed. Pass loans range from superior quality to fair quality. Business Banking Grading System Business Banking loans are graded as either Classified or Non-classified: ● Classified Classified loans are inadequately protected by the current worth and paying capacity of the obligor or, if applicable, the collateral pledged. These loans have a well-defined weakness or weaknesses, that jeopardize the liquidation of the debt or in some cases make collection or liquidation in full, on the basis of currently existing facts, conditions and values, highly questionable and improbable. They are characterized by the distinct possibility that the Company will sustain some loss if the deficiencies are not corrected. Classified loans have a high probability of payment default or a high probability of total or substantial loss. These loans require more intensive supervision by management and are generally characterized by current or expected unprofitable operations, inadequate debt service coverage, inadequate liquidity or marginal capitalization. Repayment may depend on collateral or other credit risk mitigants. When the likelihood of full collection of interest and principal may be in doubt, Classified loans are considered to have a nonaccrual status. In some cases, Classified loans are considered uncollectable and of such little value that their continuance as assets is not warranted. ● Non-classified Loans graded as Non-classified encompass all loans not graded as Classified. Non-classified loans are in compliance with loan covenants and payments are generally made as agreed. Consumer and Residential Real Estate Grading System Consumer and Residential Real Estate loans are graded as either Nonperforming or Performing. ● Nonperforming Nonperforming loans are loans that are 1) over 90 days past due and interest is still accruing or 2) on nonaccrual status. ● Performing All loans not meeting any of these criteria are considered Performing.
Troubled Debt Restructuring	Troubled Debt Restructured Loans When the Company modifies a loan in a troubled debt restructuring, such modifications include one or a combination of the following: an extension of the maturity date at a stated rate of interest lower than the current market rate for new debt with similar risk; temporary reduction in the interest rate or change in scheduled payment amount. Residential Real Estate and Consumer TDRs occurring during 2018 and 2017 were due to the reduction in the interest rate or extension of the term. Commercial TDRs during 2018 and 2017 were both a reduction of the interest rate and change in terms. When the Company modifies a loan in a troubled debt restructuring, management measures for impairment, if any, based on the present value of the expected future cash flows, discounted at the contractual interest rate of the original loan agreement, except when the sole (remaining) source of repayment for the loan is the operation or liquidation of the collateral. In these cases, management uses the current fair value of the collateral, less selling costs. If management determines that the value of the modified loan is less than the recorded investment in the loan an impairment charge would be recognized.

Defined Benefit Post-Retireme_2

Defined Benefit Post-Retirement Plans (Policies)	9 Months Ended
	Sep. 30, 2018
Defined Benefit Post-Retirement Plans [Abstract]
Postemployment Benefit Plans, Policy	The Company has a qualified, noncontributory, defined benefit pension plan (“the Plan”) covering substantially all of its employees at September 30, 2018. Benefits paid from the plan are based on age, years of service, compensation, social security benefits and are determined in accordance with defined formulas. The Company’s policy is to fund the Plan in accordance with Employee Retirement Income Security Act of 1974 standards. Assets of the Plan are invested in publicly traded stocks and mutual funds. In addition to the Plan, the Company also provides supplemental employee retirement plans to certain current and former executives. The Company also assumed supplemental retirement plans for certain current and former executives of Alliance Financial Corporation (“Alliance”) when the Company acquired Alliance. These supplemental employee retirement plans and the Plan are collectively referred to herein as “Pension Benefits.” In addition, the Company provides certain health care benefits for retired employees. Benefits are accrued over the employees’ active service period. Only employees that were employed by the Company on or before January 1, 2000 are eligible to receive post-retirement health care benefits. In addition, the Company assumed post-retirement medical life insurance benefits for certain Alliance employees, retirees and their spouses, if applicable, in the Alliance acquisition. These post-retirement benefits are referred to herein as “Other Benefits.” The Company made no voluntary contributions to the pension and other benefits plans during the three and nine months ended September 30, 2018 and 2017.

Earnings Per Share (Policies)

Earnings Per Share (Policies)	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Earnings Per Share	Basic earnings per share (“EPS”) excludes dilution and is computed by dividing income available to common stockholders by the weighted average number of common shares outstanding for the period. Diluted EPS reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock or resulted in the issuance of common stock that then shared in the earnings of the entity (such as the Company’s dilutive stock options and restricted stock units).

Fair Value Measurements and F_2

Fair Value Measurements and Fair Value of Financial Instruments (Policies)	9 Months Ended
	Sep. 30, 2018
Fair Value Measurements and Fair Value of Financial Instruments [Abstract]
Fair Value of Financial Instruments, Policy	GAAP states that fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. Fair value measurements are not adjusted for transaction costs. A fair value hierarchy exists within GAAP that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are described below: Level 1 - Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; Level 2 - Quoted prices for similar assets or liabilities in active markets, quoted prices in markets that are not active or inputs that are observable, either directly or indirectly, for substantially the full term of the asset or liability; Level 3 - Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity). A financial instrument’s level within the fair value hierarchy is based on the lowest level of input that is significant to the fair value measurement. The types of instruments valued based on quoted market prices in active markets include most U.S. government and agency securities, many other sovereign government obligations, liquid mortgage products, active listed equities and most money market securities. Such instruments are generally classified within Level 1 or Level 2 of the fair value hierarchy. The Company does not adjust the quoted prices for such instruments. The types of instruments valued based on quoted prices in markets that are not active, broker or dealer quotations or alternative pricing sources with reasonable levels of price transparency include most investment-grade and high-yield corporate bonds, less liquid mortgage products, less liquid agency securities, less liquid listed equities, state, municipal and provincial obligations and certain physical commodities. Such instruments are generally classified within Level 2 of the fair value hierarchy. Certain common equity securities are reported at fair value utilizing Level 1 inputs (exchange quoted prices). Other investment securities are reported at fair value utilizing Level 1 and Level 2 inputs. The prices for Level 2 instruments are obtained through an independent pricing service or dealer market participants with whom the Company has historically transacted both purchases and sales of investment securities. Prices obtained from these sources include prices derived from market quotations and matrix pricing. The fair value measurements consider observable data that may include dealer quotes, market spreads, cash flows, the U.S. Treasury yield curve, live trading levels, trade execution data, market consensus prepayment speeds, credit information and the bond’s terms and conditions, among other things. Management reviews the methodologies used in pricing the securities by its third party providers. Level 3 is for positions that are not traded in active markets or are subject to transfer restrictions, valuations are adjusted to reflect illiquidity and/or non-transferability and such adjustments are generally based on available market evidence. In the absence of such evidence, management’s best estimate will be used. Management’s best estimate consists of both internal and external support on certain Level 3 investments. Subsequent to inception, management only changes Level 3 inputs and assumptions when corroborated by evidence such as transactions in similar instruments, completed or pending third-party transactions in the underlying investment or comparable entities, subsequent rounds of financing, recapitalizations and other transactions across the capital structure, offerings in the equity or debt markets and changes in financial ratios or cash flows. GAAP requires disclosure of assets and liabilities measured and recorded at fair value on a non-recurring basis such as goodwill, loans held for sale, other real estate owned, collateral-dependent impaired loans, mortgage servicing rights and HTM securities. The only non-recurring fair value measurements recorded during the three and nine month periods ended September 30, 2018 and the year ended December 31, 2017 were related to impaired loans, write-down of other real estate owned and impairments of goodwill and intangible assets. The Company uses the fair value of underlying collateral, less costs to sell, to estimate the specific reserves for collateral dependent impaired loans. The appraisals may be adjusted by management for qualitative factors such as economic conditions and estimated liquidation expenses ranging from 10% to 35%. Based on the valuation techniques used, the fair value measurements for collateral dependent impaired loans are classified as Level 3. Interest Rate Swaps The Company enters into interest rate swaps to facilitate customer transactions and meet their financing needs. These swaps are considered derivatives, but are not designated in hedging relationships. These instruments have interest rate and credit risk associated with them. To mitigate the interest rate risk, the Company enters into offsetting interest rate swaps with counterparties. The counterparty swaps are also considered derivatives and are also not designated in hedging relationships. Interest rate swaps are recorded within other assets or other liabilities on the unaudited interim consolidated balance sheet at their estimated fair value. Changes to the fair value of assets and liabilities arising from these derivatives are included, net, in other operating income in the unaudited interim consolidated statement of income. At September 30, 2018 the notional amount of these customer derivative agreements and the offsetting derivative counterparty positions each totaled $630.2 million and the fair values included in other assets and other liabilities on the unaudited interim consolidated balance sheet applicable to these agreements amounted to $20.0 million. At December 31, 2017, the notional amount of these customer derivative agreements and the offsetting derivative counterparty positions each totaled $481.2 million and the fair values included in other assets and other liabilities on the unaudited interim consolidated balance sheet applicable to these agreements amounted to $0.2 million. Fair value estimates are made at a specific point in time, based on relevant market information and information about the financial instrument. These estimates do not reflect any premium or discount that could result from offering for sale at one time the Company’s entire holdings of a particular financial instrument. Because no market exists for a significant portion of the Company’s financial instruments, fair value estimates are based on judgments regarding future expected loss experience, current economic conditions, risk characteristics of various financial instruments and other factors. These estimates are subjective in nature and involve uncertainties and matters of significant judgment and therefore cannot be determined with precision. Changes in assumptions could significantly affect the estimates. Fair value estimates are based on existing on and off-balance sheet financial instruments without attempting to estimate the value of anticipated future business and the value of assets and liabilities that are not considered financial instruments. For example, the Company has a substantial trust and investment management operation that contributes net fee income annually. The trust and investment management operation is not considered a financial instrument and its value has not been incorporated into the fair value estimates. Other significant assets and liabilities include the benefits resulting from the low-cost funding of deposit liabilities as compared to the cost of borrowing funds in the market and premises and equipment. In addition, the tax ramifications related to the realization of the unrealized gains and losses can have a significant effect on fair value estimates and have not been considered in the estimate of fair value. HTM Securities The fair value of the Company’s investment HTM securities is primarily measured using information from a third party pricing service. The fair value measurements consider observable data that may include dealer quotes, market spreads, cash flows, the U.S. Treasury yield curve, live trading levels, trade execution data, market consensus prepayment speeds, credit information and the bond’s terms and conditions, among other things. Net Loans The fair value of the Company’s loans was estimated by discounting the expected future cash flows using the current interest rates at which similar loans would be made for the same remaining maturities, in accordance with the exit price notion as defined by Financial Accounting Standards Board (“FASB”) Accounting Standard Codification (“ASC”) 820, Fair Value Measurement Financial Instruments - Overall (Subtopic 825-10) - Recognition and Measurement of Financial Assets and Financial Liabilities Time Deposits The fair value of time deposits was estimated using a discounted cash flow approach that applies prevailing market interest rates for similar maturity instruments. The fair values of the Company’s time deposit liabilities do not take into consideration the value of the Company’s long-term relationships with depositors, which may have significant value. Long-Term Debt The fair value of long-term debt was estimated using a discounted cash flow approach that applies prevailing market interest rates for similar maturity instruments. Junior Subordinated Debt The fair value of junior subordinated debt has been estimated using a discounted cash flow analysis.

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Policies)	9 Months Ended
	Sep. 30, 2018
Revenue from Contracts with Customers [Abstract]
Revenue Recognition	Effective January 1, 2018, the Company adopted FASB ASU 2014-09, Revenue from Contracts with Customers (ASC Topic 606) Insurance and Other Financial Services Revenue Insurance and other financial services revenue primarily consists of commissions received on insurance and brokered investment product sales. The Company acts as an intermediary between the Company’s customer and the insurance carrier. The Company’s performance obligation is generally satisfied upon the issuance of the annuity policy. Shortly after the policy is issued, the carrier remits the commission payment to the Company, and the Company recognizes the revenue. The Company does not earn a significant amount of trailing commission fees on insurance or brokered investment product sales. The majority of the trailing commission fees are calculated based on a percentage of market value of a period end and revenue is recognized when an investment product’s market value can be determined. Service Charges on Deposit Accounts Service charges on deposit accounts consist of overdraft fees, monthly service fees, check orders and other deposit account related fees. Overdraft, monthly service, check orders and other deposit account related fees are transactional based, and therefore, the Company’s performance obligation is satisfied, and related revenue recognized, at a point in time. Payment for service charges on deposit accounts is primarily received immediately or in the following month through a direct charge to customers’ accounts. ATM and Debit Card Fees ATM fees are primarily generated when a Company cardholder uses a non-Company ATM or a non-Company cardholder uses a Company ATM. Debit card income is primarily comprised of interchange fees earned whenever the Company’s debit cards are processed through card payment networks. The Company’s performance obligations for these revenue streams are satisfied, and related revenue recognized, when the services are rendered or upon completion. Payment is typically received immediately or in the following month. Retirement Plan Administration Fees Retirement plan administration fees are primarily generated for services related to the recordkeeping, administration and plan design solutions of defined benefit, defined contribution and revenue sharing plans. Revenue is recognized in arrears for services already provided in accordance with fees established in contracts with customers or based on rates agreed to with investment trade platforms based on ending investment balances held. The Company’s performance obligation is satisfied, and related revenue recognized based on services completed or ending investment balances, for which receivables are recorded at the time of revenue recognition. Trust Trust and asset management income is primarily comprised of fees earned from the management and administration of trusts, pensions and other customer assets. The Company’s performance obligation is generally satisfied with the resulting fees recognized monthly, based upon services completed or the month-end market value of the assets under management and the applicable fee rate. Payment is generally received shortly after services are rendered or a few days after month end through a direct charge to customers’ accounts. The Company does not earn performance-based incentives. Other Other noninterest income consists of other recurring revenue streams such as account and loan fees, interest rate swap fees, safety deposit box rental fees and other miscellaneous revenue streams. These revenue streams are primarily transactional based and payment is received immediately or in the following month, and therefore, the Company’s performance obligation is satisfied, and related revenue recognized, at a point in time. Contract Balances A contract asset balance occurs when an entity performs a service for a customer before the customer pays consideration or before payment is due, which would result in contract receivables or assets, respectively. A contract liability balance is an entity’s obligation to transfer a service to a customer for which the entity has already received payment or for which payment is due from the customer. The Company’s noninterest revenue streams are largely based on transactional activity, or standard month-end revenue accruals such as asset management fees based on month-end market values. Consideration is often received immediately or shortly after the Company satisfies its performance obligation and revenue is recognized. The Company does not typically enter into long-term revenue contracts with customers, and therefore, does not experience significant contract balances. As of September 30, 2018 and December 31, 2017, the Company did not have any significant contract balances. Contract Acquisition Costs ASC 606 requires the capitalization, and subsequently amortization into expense, certain incremental costs of obtaining a contract with a customer if these costs are expected to be recovered. The incremental costs of obtaining a contract are those costs that an entity incurs to obtain a contract with a customer that it would not have incurred if the contract had not been obtained. The Company elected the practical expedient, which allows immediate expensing of contract acquisition costs when the asset that would have resulted from capitalizing these costs would have been amortized in one year or less, and did not capitalize any contract acquisition costs upon adoption of ASC 606 as of or during the three and nine months ended September 30, 2018.

Recent Accounting Pronounceme_2

Recent Accounting Pronouncements (Policies)	9 Months Ended
	Sep. 30, 2018
Recent Accounting Pronouncements [Abstract]
Recent Accounting Pronouncements	Recently Adopted Accounting Standards Effective January 1, 2018, the Company early adopted the provisions of FASB ASU 2018-02, Income Statement – Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income Effective January 1, 2018, the Company early adopted the provisions of FASB ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities adoption did not have an impact on the consolidated financial statements and related disclosures. Effective January 1, 2018, the Company adopted the provisions of FASB ASU 2017-09, Compensation-Stock Compensation (Topic 718) Effective January 1, 2018, the Company adopted the provisions of FASB ASU 2017-07, Compensation – Retirement Benefits (Topic 715) Effective January 1, 2018, the Company adopted the provisions of FASB ASU 2017-05, Other Income – Gains and Losses from the Derecognition of Nonfinancial Assets (Subtopic 610-20) Effective January 1, 2018, the Company adopted the provisions of FASB ASU 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business, adoption did not have an impact on the consolidated financial statements and related disclosures. Effective January 1, 2018, the Company adopted the provisions of FASB Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments) The amendments of ASU 2016-15 were applied on a retrospective adoption did not have an impact on the consolidated financial statements and related disclosures. Effective January 1, 2018, the Company adopted the provisions of FASB Financial Instruments - Overall (Subtopic 825-10) – Recognition and Measurement of Financial Assets and Financial Liabilities Effective January 1, 2018, the Company adopted the provisions of FASB ipal versus Agent Considerations (Reporting Revenue Gross versus Net) Identifying Performance Obligations and Licensing Narrow-Scope Improvements and Practical Expedients, Technical Corrections and Improvements to Topic 606 - Revenue from Contract with Customers Management determined that the majority of revenue earned by the Company is from revenue streams not included in the scope of this standard such as interest earned from loans, investment securities and bank owned life insurance income. For applicable revenue streams such as ATM and debit card fees, insurance, other financial services revenue, service charges on deposit accounts, retirement plan administration fees and trust fees, management reviewed the applicable contracts provisions and applied the principles in the new standard for revenue recognition. The amendments of ASU 2014-09 were applied on a modified retrospective basis. There was no cumulative effect adjustment as of January 1, 2018. The adoption of ASU 2014-09 and all related ASU updates to ASC 606 did not have a significant impact on the consolidated financial statements and related disclosures as of and for three and nine months ended September 30, 2018. Refer to footnote 10, Revenue from Contracts with Customers, for more information.
Accounting Standards Issued Not Yet Adopted	Accounting Standards Issued Not Yet Adopted In August 2018, the FASB issued ASU 2018-13, Fair value Measurement (Topic 820) – Disclosure Framework – Changes to the Disclosure Requirements for Fair value Measurement. In February 2018, the FASB issued ASU 2018-03, Technical Correction and Improvement to Financial Instruments – Overall (Subtopic 825-10) In March 2017, the FASB issued ASU 2017-08, Receivables – Nonrefundable Fees and Other Costs (Subtopic 310-20) In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) Leases (Topic 842): Land Easement Practical Expedient for Transition to Topic 842 Codification Improvements to Topic 842, Leases Targeted Improvements

Securities (Tables)

Securities (Tables)	9 Months Ended
	Sep. 30, 2018
Securities [Abstract]
Amortized Cost, Estimated Fair Value, and Unrealized Gains and Losses of Securities Available for Sale	The amortized cost, estimated fair value and unrealized gains (losses) of available for sale (“AFS”) securities are as follows: (In thousands) Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value September 30, 2018 Federal agency $ 84,974 $ - $ 1,712 $ 83,262 State & municipal 36,841 13 387 36,467 Mortgage-backed: Government-sponsored enterprises 479,852 207 16,171 463,888 U.S. government agency securities 29,422 204 1,106 28,520 Collateralized mortgage obligations: Government-sponsored enterprises 461,148 222 19,860 441,510 U.S. government agency securities 49,208 115 1,896 47,427 Total AFS securities $ 1,141,445 $ 761 $ 41,132 $ 1,101,074 December 31, 2017 Federal agency $ 109,862 $ - $ 963 $ 108,899 State & municipal 42,171 62 277 41,956 Mortgage-backed: Government-sponsored enterprises 530,392 1,406 3,345 528,453 U.S. government agency securities 26,363 334 223 26,474 Collateralized mortgage obligations: Government-sponsored enterprises 496,033 254 10,114 486,173 U.S. government agency securities 50,721 165 1,065 49,821 Equity securities 10,623 3,672 146 14,149 Total AFS securities $ 1,266,165 $ 5,893 $ 16,133 $ 1,255,925
Amortized Cost, Estimated Fair Value, and Unrealized Gains and Losses of Securities Held to Maturity	The amortized cost, estimated fair value and unrealized gains (losses) of held to maturity (“HTM”) securities are as follows: (In thousands) Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value September 30, 2018 Federal agency $ 9,995 $ - $ 46 $ 9,949 Mortgage-backed: Government-sponsored enterprises 87,743 - 4,075 83,668 U.S. government agency securities 15,241 36 69 15,208 Collateralized mortgage obligations: Government-sponsored enterprises 268,044 31 7,080 260,995 U.S. government agency securities 29,401 4 67 29,338 State & municipal 249,525 90 3,041 246,574 Total HTM securities $ 659,949 $ 161 $ 14,378 $ 645,732 December 31, 2017 Mortgage-backed: Government-sponsored enterprises $ 96,357 $ 85 $ 810 $ 95,632 U.S. government agency securities 418 57 - 475 Collateralized mortgage obligations: Government-sponsored enterprises 186,327 224 2,577 183,974 State & municipal 200,971 1,439 620 201,790 Total HTM securities $ 484,073 $ 1,805 $ 4,007 $ 481,871
Investment Securities with Unrealized Losses	The following table sets forth information with regard to investment securities with unrealized losses segregated according to the length of time the securities had been in a continuous unrealized loss position: Less than 12 months 12 months or longer Total (In thousands) Fair Value Unrealized Losses Number of Positions Fair Value Unrealized Losses Number of Positions Fair Value Unrealized Losses Number of Positions As of September 30, 2018 AFS securities: Federal agency $ 39,069 $ (916 ) 4 $ 44,193 $ (796 ) 4 $ 83,262 $ (1,712 ) 8 State & municipal 12,347 (115 ) 22 16,165 (272 ) 25 28,512 (387 ) 47 Mortgage-backed 297,802 (9,061 ) 72 178,186 (8,215 ) 48 475,988 (17,276 ) 120 Collateralized mortgage obligations 83,566 (1,816 ) 16 384,459 (19,941 ) 70 468,025 (21,757 ) 86 Total securities with unrealized losses $ 432,784 $ (11,908 ) 114 $ 623,003 $ (29,224 ) 147 $ 1,055,787 $ (41,132 ) 261 HTM securities: Federal agency $ 9,949 $ (46 ) 2 $ - $ - - $ 9,949 $ (46 ) 2 Mortgage-backed 55,712 (1,678 ) 5 42,778 (2,466 ) 4 98,490 (4,144 ) 9 Collateralized mortgage obligations 153,768 (2,195 ) 22 97,515 (4,952 ) 16 251,283 (7,147 ) 38 State & municipal 84,258 (1,276 ) 134 27,384 (1,765 ) 41 111,642 (3,041 ) 175 Total securities with unrealized losses $ 303,687 $ (5,195 ) 163 $ 167,677 $ (9,183 ) 61 $ 471,364 $ (14,378 ) 224 As of December 31, 2017 AFS securities: Federal agency $ 64,653 $ (242 ) 5 $ 44,246 $ (721 ) 4 $ 108,899 $ (963 ) 9 State & municipal 23,566 (200 ) 39 5,994 (77 ) 8 29,560 (277 ) 47 Mortgage-backed 317,630 (2,381 ) 55 58,316 (1,187 ) 24 375,946 (3,568 ) 79 Collateralized mortgage obligations 227,917 (2,658 ) 35 275,303 (8,521 ) 42 503,220 (11,179 ) 77 Equity securities - - - 2,959 (146 ) 1 2,959 (146 ) 1 Total securities with unrealized losses $ 633,766 $ (5,481 ) 134 $ 386,818 $ (10,652 ) 79 $ 1,020,584 $ (16,133 ) 213 HTM securities: Mortgage-backed $ 15,477 $ (140 ) 2 $ 33,703 $ (670 ) 2 $ 49,180 $ (810 ) 4 Collateralized mortgage obligations 118,476 (1,064 ) 17 37,614 (1,513 ) 6 156,090 (2,577 ) 23 State & municipal 22,387 (132 ) 40 15,720 (488 ) 24 38,107 (620 ) 64 Total securities with unrealized losses $ 156,340 $ (1,336 ) 59 $ 87,037 $ (2,671 ) 32 $ 243,377 $ (4,007 ) 91
Gains and Losses on Equity Securities	The following tables set forth information with regard to gains and losses on equity securities at September 30, 2018: (In thousands) Three months ended September 30, 2018 Nine months ended September 30, 2018 Net gains and losses recognized on equity securities $ 412 $ 575 Less: Net gains and losses recognized during the period on equity securities sold during the period 511 555 Unrealized gains and losses recognized on equity securities still held $ (99 ) $ 20
Contractual Maturities of Debt Securities	The following tables set forth information with regard to contractual maturities of debt securities at September 30, 2018: (In thousands) Amortized Estimated AFS debt securities: Within one year $ 46,641 $ 46,521 From one to five years 86,348 84,188 From five to ten years 176,260 171,240 After ten years 832,196 799,125 Total AFS debt securities $ 1,141,445 $ 1,101,074 HTM debt securities: Within one year $ 89,011 $ 89,011 From one to five years 53,217 53,177 From five to ten years 215,931 209,974 After ten years 301,790 293,570 Total HTM debt securities $ 659,949 $ 645,732

Allowance for Loan Losses and_3

Allowance for Loan Losses and Credit Quality of Loans (Tables)	9 Months Ended
	Sep. 30, 2018
Allowance for Loan Losses and Credit Quality of Loans [Abstract]
Portfolio and Class Segments	Portfolio Class - 2018 Class - 2017 Commercial Loans Commercial and Industrial Commercial Commercial Real Estate Commercial Real Estate Business Banking Agricultural Agricultural Real Estate Business Banking Consumer Loans Dealer Finance Indirect Specialty Lending Home Equity Direct Direct Residential Real Estate
Allowance for Loan Losses by Portfolio	The following tables illustrate the changes in the allowance for loan losses by our portfolio segments: (In thousands) Commercial Loans Consumer Loans Residential Real Estate Total Balance as of June 30, 2018 $ 31,059 $ 36,479 $ 4,912 $ 72,450 Charge-offs (823 ) (6,818 ) (123 ) (7,764 ) Recoveries 410 1,602 81 2,093 Provision 1,086 6,044 (1,104 ) 6,026 Ending Balance as of September 30, 2018 $ 31,732 $ 37,307 $ 3,766 $ 72,805 Balance as of June 30, 2017 $ 24,428 $ 35,523 $ 6,649 $ 66,600 Charge-offs (574 ) (6,979 ) (421 ) (7,974 ) Recoveries 266 1,446 123 1,835 Provision 1,434 6,197 258 7,889 Ending Balance as of September 30, 2017 $ 25,554 $ 36,187 $ 6,609 $ 68,350 (In thousands) Commercial Loans Consumer Loans Residential Real Estate Total Balance as of December 31, 2017 $ 27,606 $ 36,830 $ 5,064 $ 69,500 Charge-offs (2,535 ) (21,947 ) (513 ) (24,995 ) Recoveries 780 4,946 274 6,000 Provision 5,881 17,478 (1,059 ) 22,300 Ending Balance as of September 30, 2018 $ 31,732 $ 37,307 $ 3,766 $ 72,805 Balance as of December 31, 2016 $ 25,444 $ 33,375 $ 6,381 $ 65,200 Charge-offs (2,991 ) (19,742 ) (1,717 ) (24,450 ) Recoveries 919 3,680 166 4,765 Provision 2,182 18,874 1,779 22,835 Ending Balance as of September 30, 2017 $ 25,554 $ 36,187 $ 6,609 $ 68,350 The following tables illustrate the allowance for loan losses and the recorded investment by portfolio segments: (In thousands) Commercial Loans Consumer Loans Residential Real Estate Total As of September 30, 2018 Allowance for loan losses $ 31,732 $ 37,307 $ 3,766 $ 72,805 Allowance for loans individually evaluated for impairment 25 - - 25 Allowance for loans collectively evaluated for impairment $ 31,707 $ 37,307 $ 3,766 $ 72,780 Ending balance of loans $ 3,212,577 $ 2,301,198 $ 1,373,487 $ 6,887,262 Ending balance of originated loans individually evaluated for impairment 5,077 7,760 6,445 19,282 Ending balance of acquired loans collectively evaluated for impairment 153,808 33,994 153,073 340,875 Ending balance of originated loans collectively evaluated for impairment $ 3,053,692 $ 2,259,444 $ 1,213,969 $ 6,527,105 As of December 31, 2017 Allowance for loan losses $ 27,606 $ 36,830 $ 5,064 $ 69,500 Allowance for loans individually evaluated for impairment 57 - - 57 Allowance for loans collectively evaluated for impairment $ 27,549 $ 36,830 $ 5,064 $ 69,443 Ending balance of loans $ 3,028,269 $ 2,234,349 $ 1,321,021 $ 6,583,639 Ending balance of originated loans individually evaluated for impairment 5,876 8,432 6,830 21,138 Ending balance of acquired loans collectively evaluated for impairment 187,313 43,906 170,472 401,691 Ending balance of originated loans collectively evaluated for impairment $ 2,835,080 $ 2,182,011 $ 1,143,719 $ 6,160,810
Past Due and Nonperforming Loans by Loan Class	The following tables set forth information with regard to past due and nonperforming loans by loan class: 31-60 Days Past Due Accruing 61-90 Days Past Due Accruing Greater Than 90 Days Past Due Accruing Total Past Due Accruing Nonaccrual Current Recorded As of September 30, 2018 Originated Commercial Loans: C&I $ 209 $ 41 $ - $ 250 $ 908 $ 857,782 $ 858,940 CRE 1,133 - - 1,133 3,637 1,708,369 1,713,139 Business Banking 1,318 98 - 1,416 5,754 479,520 486,690 Total Commercial Loans $ 2,660 $ 139 $ - $ 2,799 $ 10,299 $ 3,045,671 $ 3,058,769 Consumer Loans: Dealer Finance $ 14,364 $ 2,039 $ 1,252 $ 17,655 $ 2,062 $ 1,209,880 $ 1,229,597 Specialty Lending 3,037 2,155 1,544 6,736 - 514,660 521,396 Direct 3,313 949 434 4,696 2,541 508,974 516,211 Total Consumer Loans $ 20,714 $ 5,143 $ 3,230 $ 29,087 $ 4,603 $ 2,233,514 $ 2,267,204 Residential Real Estate $ 1,366 $ 219 $ 1,231 $ 2,816 $ 6,106 $ 1,211,492 $ 1,220,414 Total Originated Loans $ 24,740 $ 5,501 $ 4,461 $ 34,702 $ 21,008 $ 6,490,677 $ 6,546,387 Acquired Commercial Loans: C&I $ - $ - $ - $ - $ - $ 30,871 $ 30,871 CRE - - - - 2 87,827 87,829 Business Banking 425 - 240 665 611 33,832 35,108 Total Commercial Loans $ 425 $ - $ 240 $ 665 $ 613 $ 152,530 $ 153,808 Consumer Loans: Dealer Finance $ 4 $ - $ - $ 4 $ - $ 99 $ 103 Direct 223 14 - 237 275 33,379 33,891 Total Consumer Loans $ 227 $ 14 $ - $ 241 $ 275 $ 33,478 $ 33,994 Residential Real Estate $ 839 $ 39 $ 33 $ 911 $ 1,405 $ 150,757 $ 153,073 Total Acquired Loans $ 1,491 $ 53 $ 273 $ 1,817 $ 2,293 $ 336,765 $ 340,875 Total Loans $ 26,231 $ 5,554 $ 4,734 $ 36,519 $ 23,301 $ 6,827,442 $ 6,887,262 (In thousands) 31-60 Days Past Due Accruing 61-90 Days Past Due Accruing Greater Than 90 Days Past Due Accruing Total Past Due Accruing Nonaccrual Current Recorded Total Loans As of December 31, 2017 Originated Commercial Loans: Commercial $ - $ - $ - $ - $ 202 $ 753,577 $ 753,779 Commercial Real Estate 161 138 - 299 3,178 1,533,065 1,536,542 Agricultural 117 - - 117 1,043 34,386 35,546 Agricultural Real Estate 493 - - 493 2,736 30,905 34,134 Business Banking 1,907 597 - 2,504 5,304 473,147 480,955 Total Commercial Loans $ 2,678 $ 735 $ - $ 3,413 $ 12,463 $ 2,825,080 $ 2,840,956 Consumer Loans: Indirect $ 18,747 $ 4,033 $ 3,492 $ 26,272 $ 2,115 $ 1,642,204 $ 1,670,591 Home Equity 2,887 854 341 4,082 2,736 448,081 454,899 Direct 341 108 70 519 35 64,399 64,953 Total Consumer Loans $ 21,975 $ 4,995 $ 3,903 $ 30,873 $ 4,886 $ 2,154,684 $ 2,190,443 Residential Real Estate $ 3,730 $ 667 $ 1,262 $ 5,659 $ 5,987 $ 1,138,903 $ 1,150,549 Total Originated Loans $ 28,383 $ 6,397 $ 5,165 $ 39,945 $ 23,336 $ 6,118,667 $ 6,181,948 Acquired Commercial Loans: Commercial $ - $ - $ - $ - $ - $ 39,575 $ 39,575 Commercial Real Estate - - - - 2 106,632 106,634 Business Banking 354 - - 354 669 40,081 41,104 Total Commercial Loans $ 354 $ - $ - $ 354 $ 671 $ 186,288 $ 187,313 Consumer Loans: Indirect $ 38 $ - $ 1 $ 39 $ 22 $ 1,157 $ 1,218 Home Equity 254 34 103 391 225 39,256 39,872 Direct 6 1 1 8 23 2,785 2,816 Total Consumer Loans $ 298 $ 35 $ 105 $ 438 $ 270 $ 43,198 $ 43,906 Residential Real Estate $ 627 $ 226 $ 140 $ 993 $ 1,431 $ 168,048 $ 170,472 Total Acquired Loans $ 1,279 $ 261 $ 245 $ 1,785 $ 2,372 $ 397,534 $ 401,691 Total Loans $ 29,662 $ 6,658 $ 5,410 $ 41,730 $ 25,708 $ 6,516,201 $ 6,583,639
Impaired Loans and Specific Reserve Allocations	The following table provides information on loans specifically evaluated for impairment: September 30, 2018 December 31, 2017 (In thousands) Recorded Investment Balance (Book) Unpaid Principal Balance (Legal) Related Allowance Recorded Investment Balance (Book) Unpaid Principal Balance (Legal) Related Allowance Originated With no related allowance recorded: Commercial Loans: C&I $ 404 $ 676 $ - $ - CRE 3,629 5,616 - - Commercial - - - 251 Commercial Real Estate - - 2,211 3,979 Agricultural - - 452 465 Agricultural Real Estate - - 2,250 2,423 Business Banking 1,019 2,099 860 1,730 Total Commercial Loans $ 5,052 $ 8,391 $ 5,773 $ 8,848 Consumer Loans: Dealer Finance $ 160 $ 254 $ - $ - Direct 7,600 9,600 - - Indirect - - 131 143 Home Equity - - 8,027 9,966 Direct - - 274 274 Total Consumer Loans $ 7,760 $ 9,854 $ 8,432 $ 10,383 Residential Real Estate $ 6,445 $ 8,721 $ 6,830 $ 8,780 Total $ 19,257 $ 26,966 $ 21,035 $ 28,011 With an allowance recorded: Commercial Loans: C&I $ 25 $ 25 $ 25 $ - $ - $ - Commercial Real Estate - - - 76 82 30 Agricultural - - - 27 27 27 Total Commercial Loans $ 25 $ 25 $ 25 $ 103 $ 109 $ 57 Total Loans $ 19,282 $ 26,991 $ 25 $ 21,138 $ 28,120 $ 57 The following tables summarize the average recorded investments on loans specifically evaluated for impairment and the interest income recognized: For the three months ended September 30, 2018 September 30, 2017 (In thousands) Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized Originated Commercial Loans: C&I $ 433 $ - $ - $ - CRE 3,645 32 - - Commercial - - 1,000 - Commercial Real Estate - - 2,415 48 Agricultural - - 115 - Agricultural Real Estate - - 1,505 11 Business Banking 1,024 4 955 2 Total Commercial Loans $ 5,102 $ 36 $ 5,990 $ 61 Consumer Loans: Dealer Finance $ 177 $ 4 $ - $ - Direct 7,730 102 - - Indirect - - 35 1 Home Equity - - 8,159 111 Direct - - 119 2 Total Consumer Loans $ 7,907 $ 106 $ 8,313 $ 114 Residential Real Estate $ 6,519 $ 68 $ 6,633 $ 82 Total Originated Loans $ 19,528 $ 210 $ 20,936 $ 257 Total Loans $ 19,528 $ 210 $ 20,936 $ 257 For the nine months ended September 30, 2018 September 30, 2017 (In thousands) Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized Originated Commercial Loans: C&I $ 449 $ 1 $ - $ - CRE 3,999 96 - - Commercial - - 2,393 - Commercial Real Estate - - 3,906 93 Agricultural - - 147 1 Agricultural Real Estate - - 1,545 32 Business Banking 998 12 837 7 Total Commercial Loans $ 5,446 $ 109 $ 8,828 $ 133 Consumer Loans: Dealer Finance $ 187 $ 8 $ - $ - Direct 7,953 317 - - Indirect - - 22 2 Home Equity - - 8,274 331 Direct - - 119 2 Total Consumer Loans $ 8,140 $ 325 $ 8,415 $ 335 Residential Real Estate $ 6,719 $ 212 $ 6,425 $ 211 Total Originated Loans $ 20,305 $ 646 $ 23,668 $ 679 Acquired Commercial Loans: Commercial Real Estate $ - $ - $ 121 $ - Total Commercial Loans $ - $ - $ 121 $ - Total Acquired Loans $ - $ - $ 121 $ - Total Loans $ 20,305 $ 646 $ 23,789 $ 679
Financing Receivable Credit Quality by Loan Class	The following tables illustrate the Company’s credit quality by loan class: (In thousands) As of September 30, 2018 Originated Commercial Credit Exposure By Internally Assigned Grade: C&I CRE Total Pass $ 805,333 $ 1,660,900 $ 2,466,233 Special Mention 33,557 16,762 50,319 Substandard 20,050 35,477 55,527 Total $ 858,940 $ 1,713,139 $ 2,572,079 Business Banking Credit Exposure By Internally Assigned Grade: Business Banking Total Non-classified $ 474,252 $ 474,252 Classified 12,438 12,438 Total $ 486,690 $ 486,690 Consumer Credit Exposure By Payment Activity: Dealer Finance Specialty Lending Direct Total Performing $ 1,226,283 $ 519,852 $ 513,236 $ 2,259,371 Nonperforming 3,314 1,544 2,975 7,833 Total $ 1,229,597 $ 521,396 $ 516,211 $ 2,267,204 Residential Real Estate Credit Exposure By Payment Activity: Residential Real Estate Total Performing $ 1,213,077 $ 1,213,077 Nonperforming 7,337 7,337 Total $ 1,220,414 $ 1,220,414 Acquired Commercial Credit Exposure By Internally Assigned Grade: C&I CRE Total Pass $ 27,046 $ 87,091 $ 114,137 Special Mention 3,825 93 3,918 Substandard - 645 645 Total $ 30,871 $ 87,829 $ 118,700 Business Banking Credit Exposure By Internally Assigned Grade: Business Banking Total Non-classified $ 32,098 $ 32,098 Classified 3,010 3,010 Total $ 35,108 $ 35,108 Consumer Credit Exposure By Payment Activity: Dealer Finance Direct Total Performing $ 103 $ 33,616 $ 33,719 Nonperforming - 275 275 Total $ 103 $ 33,891 $ 33,994 Residential Real Estate Credit Exposure By Payment Activity: Residential Real Estate Total Performing $ 151,635 $ 151,635 Nonperforming 1,438 1,438 Total $ 153,073 $ 153,073 (In thousands) As of December 31, 2017 Originated Commercial Credit Exposure By Internally Assigned Grade: Commercial Commercial Real Estate Agricultural Agricultural Real Estate Total Pass $ 708,567 $ 1,481,926 $ 31,142 $ 23,381 $ 2,245,016 Special Mention 30,337 28,264 2,294 2,441 63,336 Substandard 14,875 26,352 2,110 8,312 51,649 Total $ 753,779 $ 1,536,542 $ 35,546 $ 34,134 $ 2,360,001 Business Banking Credit Exposure By Internally Assigned Grade: Business Total Non-classified $ 468,898 $ 468,898 Classified 12,057 12,057 Total $ 480,955 $ 480,955 Consumer Credit Exposure By Payment Activity: Indirect Home Equity Direct Total Performing $ 1,664,984 $ 451,822 $ 64,848 $ 2,181,654 Nonperforming 5,607 3,077 105 8,789 Total $ 1,670,591 $ 454,899 $ 64,953 $ 2,190,443 Residential Real Estate Credit Exposure By Payment Activity: Residential Real Estate Total Performing $ 1,143,300 $ 1,143,300 Nonperforming 7,249 7,249 Total $ 1,150,549 $ 1,150,549 Acquired Commercial Credit Exposure By Internally Assigned Grade: Commercial Commercial Real Estate Total Pass $ 37,825 $ 103,248 $ 141,073 Special Mention 425 498 923 Substandard 1,325 2,888 4,213 Total $ 39,575 $ 106,634 $ 146,209 Business Banking Credit Exposure By Internally Assigned Grade: Business Banking Total Non-classified $ 38,236 $ 38,236 Classified 2,868 2,868 Total $ 41,104 $ 41,104 Consumer Credit Exposure By Payment Activity: Indirect Home Equity Direct Total Performing $ 1,195 $ 39,544 $ 2,792 $ 43,531 Nonperforming 23 328 24 375 Total $ 1,218 $ 39,872 $ 2,816 $ 43,906 Residential Real Estate Credit Exposure By Payment Activity: Residential Real Estate Total Performing $ 168,901 $ 168,901 Nonperforming 1,571 1,571 Total $ 170,472 $ 170,472
Troubled Debt Restructurings on Financing Receivables	The following tables illustrate the recorded investment and number of modifications for modified loans, including the recorded investment in the loans prior to a modification and the recorded investment in the loans after restructuring: Three months ended September 30, 2018 (Dollars in thousands) Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Consumer Loans: Dealer Finance 8 $ 90 $ 89 Total Consumer Loans 8 $ 90 $ 89 Total Troubled Debt Restructurings 8 $ 90 $ 89 Three months ended September 30, 2017 (Dollars in thousands) Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Consumer Loans: Indirect 1 $ 7 $ 7 Home Equity 4 189 222 Total Consumer Loans 5 $ 196 $ 229 Residential Real Estate 1 $ 518 $ 518 Total Troubled Debt Restructurings 6 $ 714 $ 747 Nine months ended September 30, 2018 (Dollars in thousands) Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Commercial Loans: Business Banking 3 $ 369 $ 371 Total Commercial Loans 3 $ 369 $ 371 Consumer Loans: Dealer Finance 15 $ 185 $ 183 Direct 2 41 41 Total Consumer Loans 17 $ 226 $ 224 Residential Real Estate 5 $ 323 $ 323 Total Troubled Debt Restructurings 25 $ 918 $ 918 Nine months ended September 30, 2017 (Dollars in thousands) Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Commercial Loans: Commercial 1 $ 3,300 $ 3,239 Business Banking 1 337 333 Total Commercial Loans 2 $ 3,637 $ 3,572 Consumer Loans: Indirect 4 $ 39 $ 37 Home Equity 8 373 414 Direct 1 120 120 Total Consumer Loans 13 $ 532 $ 571 Residential Real Estate 8 $ 1,066 $ 1,068 Total Troubled Debt Restructurings 23 $ 5,235 $ 5,211 The following tables illustrate the recorded investment and number of modifications for TDRs where a concession has been made and subsequently defaulted during the period: Three months ended September 30, 2018 Three months ended September 30, 2017 (Dollars in thousands) Number of Contracts Recorded Number of Contracts Recorded Investment Consumer Loans: Indirect - $ - 1 $ 13 Home Equity - - 12 622 Direct 17 816 - - Total Consumer Loans 17 $ 816 13 $ 635 Residential Real Estate 5 $ 398 6 $ 546 Total Troubled Debt Restructurings 22 $ 1,214 19 $ 1,181 Nine months ended September 30, 2018 Nine months ended September 30, 2017 (Dollars in thousands) Number of Contracts Recorded Investment Number of Contracts Recorded Investment Commercial Loans: Commercial - $ - 1 $ 145 Business Banking 2 258 1 329 Total Commercial Loans 2 $ 258 2 $ 474 Consumer Loans: Indirect - $ - 2 $ 19 Home Equity - - 30 1,381 Direct 35 1,740 - - Total Consumer Loans 35 $ 1,740 32 $ 1,400 Residential Real Estate 17 $ 1,239 12 $ 817 Total Troubled Debt Restructurings 54 $ 3,237 46 $ 2,691

Defined Benefit Post-Retireme_3

Defined Benefit Post-Retirement Plans (Tables)	9 Months Ended
	Sep. 30, 2018
Defined Benefit Post-Retirement Plans [Abstract]
Net Periodic Pension Benefits and Other Benefit Costs	The components of expense for Pension Benefits and Other Benefits are set forth below: Pension Benefits Other Benefits Three months ended September 30, Three months ended September 30, (In thousands) 2018 2017 2018 2017 Components of net periodic (benefit) cost Service cost $ 415 $ 329 $ 3 $ 3 Interest cost 912 1,043 82 88 Expected return on plan assets (2,119 ) (1,976 ) - - Net amortization 242 454 44 26 Total net periodic (benefit) cost $ (550 ) $ (150 ) $ 129 $ 117 Pension Benefits Other Benefits Nine months ended September 30, Nine months ended September 30, (In thousands) 2018 2017 2018 2017 Components of net periodic (benefit) cost Service cost $ 1,256 $ 1,133 $ 8 $ 9 Interest cost 2,752 3,127 245 259 Expected return on plan assets (6,364 ) (5,946 ) - - Net amortization 745 1,284 131 66 Total net periodic (benefit) cost $ (1,611 ) $ (402 ) $ 384 $ 334

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Reconciliation of Basic and Diluted Earnings per Share	The following is a reconciliation of basic and diluted EPS for the periods presented in the unaudited interim consolidated statements of income: Three months ended September 30, (In thousands, except per share data) 2018 2017 Basic EPS: Weighted average common shares outstanding 43,714 43,595 Net income available to common stockholders $ 29,807 $ 22,876 Basic EPS $ 0.68 $ 0.52 Diluted EPS: Weighted average common shares outstanding 43,714 43,595 Dilutive effect of common stock options and restricted stock 337 320 Weighted average common shares and common share equivalents 44,051 43,915 Net income available to common stockholders $ 29,807 $ 22,876 Diluted EPS $ 0.68 $ 0.52 Nine months ended September 30, (In thousands, except per share data) 2018 2017 Basic EPS: Weighted average common shares outstanding 43,692 43,563 Net income available to common stockholders $ 83,914 $ 64,514 Basic EPS $ 1.92 $ 1.48 Diluted EPS: Weighted average common shares outstanding 43,692 43,563 Dilutive effect of common stock options and restricted stock 317 329 Weighted average common shares and common share equivalents 44,009 43,892 Net income available to common stockholders $ 83,914 $ 64,514 Diluted EPS $ 1.91 $ 1.47

Reclassification Adjustments _2

Reclassification Adjustments Out of Other Comprehensive Income (Loss) (Tables)	9 Months Ended
	Sep. 30, 2018
Reclassification Adjustments Out of Other Comprehensive Income (Loss) [Abstract]
Reclassification Out of Accumulated Other Comprehensive Income	The following table summarizes the reclassification adjustments out of accumulated other comprehensive income (loss) (“AOCI”): Detail About AOCI Components Amount Reclassified From AOCI Affected Line Item in the Consolidated Statement of Comprehensive Income (Loss) Three months ended (In thousands) September 30, 2018 September 30, 2017 AFS securities: Losses on AFS securities $ - $ 4 Net securities losses Amortization of unrealized gains related to securities transfer 168 212 Interest income Tax effect $ (42 ) $ (83 ) Income tax (expense) benefit Net of tax $ 126 $ 133 Cash flow hedges: Net unrealized (gains) on cash flow hedges reclassified to interest (income) $ (638 ) $ (155 ) Interest income Tax effect $ 159 $ 59 Income tax (expense) benefit Net of tax $ (479 ) $ (96 ) Pension and other benefits: Amortization of net losses $ 263 $ 481 Other noninterest expense Amortization of prior service costs 23 (1 ) Other noninterest expense Tax effect $ (71 ) $ (183 ) Income tax (expense) benefit Net of tax $ 215 $ 297 Total reclassifications during the period, net of tax $ (138 ) $ 334 Detail About AOCI Components Amount Reclassified From AOCI Affected Line item in the Consolidated Statement of Comprehensive Income (Loss) Nine months ended (In thousands) September 30, September 30, 2017 AFS securities: Losses on AFS securities $ - $ 2 Net securities losses Amortization of unrealized gains related to securities transfer 533 675 Interest income Impairment write-down of equity security - 1,312 Other noninterest income Tax effect $ (133 ) $ (760 ) Income tax (expense) benefit Net of tax $ 400 $ 1,229 Cash flow hedges: Net unrealized (gains) on cash flow hedges reclassified to interest (income) $ (1,537 ) $ (96 ) Interest income Tax effect $ 384 $ 37 Income tax (expense) benefit Net of tax $ (1,153 ) $ (59 ) Pension and other benefits: Amortization of net losses $ 809 $ 1,351 Other noninterest expense Amortization of prior service costs 67 (1 ) Other noninterest expense Tax effect $ (219 ) $ (516 ) Income tax (expense) benefit Net of tax $ 657 $ 834 Total reclassifications during the period, net of tax $ (96 ) $ 2,004

Fair Value Measurements and F_3

Fair Value Measurements and Fair Value of Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2018
Fair Value Measurements and Fair Value of Financial Instruments [Abstract]
Fair Value of Financial Assets and Liabilities Measured on a Recurring Basis	The following tables set forth the Company’s financial assets and liabilities measured on a recurring basis that were accounted for at fair value. Assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement: (In thousands) Level 1 Level 2 Level 3 September 30, 2018 Assets: AFS securities Federal Agency $ - $ 83,262 $ - $ 83,262 State & municipal - 36,467 - 36,467 Mortgage-backed - 492,408 - 492,408 Collateralized mortgage obligations - 488,937 - 488,937 Total AFS securities $ - $ 1,101,074 $ - $ 1,101,074 Equity securities 20,722 4,000 - 24,722 Derivatives - 23,682 - 23,682 Total $ 20,722 $ 1,128,756 $ - $ 1,149,478 Liabilities: Derivatives $ - $ 20,054 $ - $ 20,054 Total $ - $ 20,054 $ - $ 20,054 (In thousands) Level 1 Level 2 Level 3 December 31, 2017 Assets: AFS securities Federal Agency $ - $ 108,899 $ - $ 108,899 State & municipal - 41,956 - 41,956 Mortgage-backed - 554,927 - 554,927 Collateralized mortgage obligations - 535,994 - 535,994 Other securities 5,845 8,304 - 14,149 Total AFS securities $ 5,845 $ 1,250,080 $ - $ 1,255,925 Trading securities 11,467 - - 11,467 Derivatives - 3,732 - 3,732 Total $ 17,312 $ 1,253,812 $ - $ 1,271,124 Liabilities: Derivatives $ - $ 324 $ - $ 324 Total $ - $ 324 $ - $ 324
Fair Value of Financial Instruments by Balance Sheet Grouping	The following table sets forth information with regard to estimated fair values of financial instruments. This table excludes financial instruments for which the carrying amount approximates fair value. Financial instruments for which the fair value approximates carrying value include cash and cash equivalents, AFS securities, equity securities, trading securities, accrued interest receivable, non-maturity deposits, short-term borrowings, accrued interest payable and interest rate swaps. September 30, 2018 December 31, 2017 (In thousands) Fair Value Carrying Amount Estimated Fair Value Carrying Amount Estimated Fair Value Financial assets: HTM securities 2 $ 659,949 $ 645,732 $ 484,073 $ 481,871 Net loans 3 6,819,492 6,762,901 6,515,273 6,651,931 Financial liabilities: Time deposits 2 $ 868,569 $ 860,791 $ 806,766 $ 801,294 Long-term debt 2 73,751 72,152 88,869 88,346 Junior subordinated debt 2 101,196 102,979 101,196 104,593

Revenue from Contracts with C_3

Revenue from Contracts with Customers (Tables)	9 Months Ended
	Sep. 30, 2018
Revenue from Contracts with Customers [Abstract]
Non-interest Income	The following table presents noninterest income, segregated by revenue streams in-scope and out-of-scope of ASC 606, for three and nine months ended September 30, 2018 and 2017: Three months ended September 30, Nine months ended September 30, (In thousands) 2018 2017 2018 2017 Noninterest income In-Scope of ASC 606: Insurance and other financial services revenue $ 6,172 $ 5,536 $ 18,502 $ 17,927 Service charges on deposit accounts 4,503 4,261 12,721 12,399 ATM and debit card fees 5,906 5,557 16,995 16,025 Retirement plan administration fees 7,244 5,272 19,879 14,881 Trust 4,808 4,927 14,951 14,620 Other 3,048 3,945 11,341 10,069 Total noninterest income in-scope of ASC 606 $ 31,681 $ 29,498 $ 94,389 $ 85,921 Total noninterest income out-of-scope of ASC 606 $ 1,700 $ 1,280 $ 4,427 $ 3,911 Total noninterest income $ 33,381 $ 30,778 $ 98,816 $ 89,832

Securities, Available for Sale

Securities, Available for Sale (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Debt securities, available-for-sale [Abstract]
Amortized cost	$ 1,141,445		$ 1,141,445
Unrealized gains	761		761
Unrealized losses	41,132		41,132
Estimated fair value	1,101,074		1,101,074
Total available-for-sale securities [Abstract]
Amortized cost					$ 1,266,165
Unrealized gains					5,893
Unrealized losses					16,133
Estimated fair value	1,101,074		1,101,074		1,255,925
OTTI loss realized on equity investment	0	$ 0	0	$ 1,300
Federal Agency [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	84,974		84,974		109,862
Unrealized gains	0		0		0
Unrealized losses	1,712		1,712		963
Estimated fair value	83,262		83,262		108,899
State & Municipal [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	36,841		36,841		42,171
Unrealized gains	13		13		62
Unrealized losses	387		387		277
Estimated fair value	36,467		36,467		41,956
Mortgage-Backed, Government Sponsored Enterprises [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	479,852		479,852		530,392
Unrealized gains	207		207		1,406
Unrealized losses	16,171		16,171		3,345
Estimated fair value	463,888		463,888		528,453
Mortgage-Backed, U.S. Government Agency Securities [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	29,422		29,422		26,363
Unrealized gains	204		204		334
Unrealized losses	1,106		1,106		223
Estimated fair value	28,520		28,520		26,474
Collateralized Mortgage Obligations, Government-Sponsored Enterprises [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	461,148		461,148		496,033
Unrealized gains	222		222		254
Unrealized losses	19,860		19,860		10,114
Estimated fair value	441,510		441,510		486,173
Collateralized Mortgage Obligations, U.S. Government Agency Securities [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	49,208		49,208		50,721
Unrealized gains	115		115		165
Unrealized losses	1,896		1,896		1,065
Estimated fair value	$ 47,427		$ 47,427		49,821
Equity Securities [Member]
Equity securities, available-for-sale [Abstract]
Amortized cost					10,623
Unrealized gains					3,672
Unrealized losses					146
Estimated fair value					$ 14,149

Securities, Held to Maturity (D

Securities, Held to Maturity (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Held-to-maturity securities, fair value to amortized cost [Abstract]
Amortized cost	$ 659,949		$ 659,949		$ 484,073
Unrealized gains	161		161		1,805
Unrealized losses	14,378		14,378		4,007
Estimated fair value	645,732		645,732		481,871
Held-to-maturity securities sold, amortized cost	0	$ 800	0	$ 800
Held-to-maturity securities sold, unrealized loss	0	$ 2	0	$ 2
Amortized costs of securities available for sale and held to maturity pledged to secure public deposits	1,600,000		1,600,000		1,500,000
Amortized costs of securities AFS and HTM pledged as collateral for repurchase agreements	196,400		196,400		256,200
Federal Agency [Member]
Held-to-maturity securities, fair value to amortized cost [Abstract]
Amortized cost	9,995		9,995
Unrealized gains	0		0
Unrealized losses	46		46
Estimated fair value	9,949		9,949
Mortgage-Backed, Government Sponsored Enterprises [Member]
Held-to-maturity securities, fair value to amortized cost [Abstract]
Amortized cost	87,743		87,743		96,357
Unrealized gains	0		0		85
Unrealized losses	4,075		4,075		810
Estimated fair value	83,668		83,668		95,632
Mortgage-Backed, U.S. Government Agency Securities [Member]
Held-to-maturity securities, fair value to amortized cost [Abstract]
Amortized cost	15,241		15,241		418
Unrealized gains	36		36		57
Unrealized losses	69		69		0
Estimated fair value	15,208		15,208		475
Collateralized Mortgage Obligations, Government-Sponsored Enterprises [Member]
Held-to-maturity securities, fair value to amortized cost [Abstract]
Amortized cost	268,044		268,044		186,327
Unrealized gains	31		31		224
Unrealized losses	7,080		7,080		2,577
Estimated fair value	260,995		260,995		183,974
Collateralized Mortgage Obligations, U.S. Government Agency Securities [Member]
Held-to-maturity securities, fair value to amortized cost [Abstract]
Amortized cost	29,401		29,401
Unrealized gains	4		4
Unrealized losses	67		67
Estimated fair value	29,338		29,338
State & Municipal [Member]
Held-to-maturity securities, fair value to amortized cost [Abstract]
Amortized cost	249,525		249,525		200,971
Unrealized gains	90		90		1,439
Unrealized losses	3,041		3,041		620
Estimated fair value	$ 246,574		$ 246,574		$ 201,790

Securities, AFS Securities in C

Securities, AFS Securities in Continuous Unrealized Loss Position (Details) $ in Thousands	Sep. 30, 2018USD ($)Position	Dec. 31, 2017USD ($)Position
Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	$ 432,784	$ 633,766
12 months or longer	623,003	386,818
Total	1,055,787	1,020,584
Unrealized Loss Position, Unrealized Losses [Abstract]
Less than 12 months	(11,908)	(5,481)
12 months or longer	(29,224)	(10,652)
Total	$ (41,132)	$ (16,133)
Unrealized Loss Position, Number of Positions [Abstract]
Less than 12 months | Position	114	134
12 months or longer | Position	147	79
Total | Position	261	213
Federal Agency [Member]
Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	$ 39,069	$ 64,653
12 months or longer	44,193	44,246
Total	83,262	108,899
Unrealized Loss Position, Unrealized Losses [Abstract]
Less than 12 months	(916)	(242)
12 months or longer	(796)	(721)
Total	$ (1,712)	$ (963)
Unrealized Loss Position, Number of Positions [Abstract]
Less than 12 months | Position	4	5
12 months or longer | Position	4	4
Total | Position	8	9
State & Municipal [Member]
Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	$ 12,347	$ 23,566
12 months or longer	16,165	5,994
Total	28,512	29,560
Unrealized Loss Position, Unrealized Losses [Abstract]
Less than 12 months	(115)	(200)
12 months or longer	(272)	(77)
Total	$ (387)	$ (277)
Unrealized Loss Position, Number of Positions [Abstract]
Less than 12 months | Position	22	39
12 months or longer | Position	25	8
Total | Position	47	47
Mortgage-Backed [Member]
Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	$ 297,802	$ 317,630
12 months or longer	178,186	58,316
Total	475,988	375,946
Unrealized Loss Position, Unrealized Losses [Abstract]
Less than 12 months	(9,061)	(2,381)
12 months or longer	(8,215)	(1,187)
Total	$ (17,276)	$ (3,568)
Unrealized Loss Position, Number of Positions [Abstract]
Less than 12 months | Position	72	55
12 months or longer | Position	48	24
Total | Position	120	79
Collateralized Mortgage Obligations [Member]
Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	$ 83,566	$ 227,917
12 months or longer	384,459	275,303
Total	468,025	503,220
Unrealized Loss Position, Unrealized Losses [Abstract]
Less than 12 months	(1,816)	(2,658)
12 months or longer	(19,941)	(8,521)
Total	$ (21,757)	$ (11,179)
Unrealized Loss Position, Number of Positions [Abstract]
Less than 12 months | Position	16	35
12 months or longer | Position	70	42
Total | Position	86	77
Equity Securities [Member]
Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months		$ 0
12 months or longer		2,959
Total		2,959
Unrealized Loss Position, Unrealized Losses [Abstract]
Less than 12 months		0
12 months or longer		(146)
Total		$ (146)
Unrealized Loss Position, Number of Positions [Abstract]
Less than 12 months | Position		0
12 months or longer | Position		1
Total | Position		1

Securities, HTM Securities in C

Securities, HTM Securities in Continuous Unrealized Loss Position (Details) $ in Thousands	Sep. 30, 2018USD ($)Position	Dec. 31, 2017USD ($)Position
Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	$ 303,687	$ 156,340
12 months or longer	167,677	87,037
Total	471,364	243,377
Unrealized Loss Position, Unrealized Losses [Abstract]
Less than 12 months	(5,195)	(1,336)
12 months or longer	(9,183)	(2,671)
Total	$ (14,378)	$ (4,007)
Unrealized Loss Position, Number of Positions [Abstract]
Less than 12 months | Position	163	59
12 months or longer | Position	61	32
Total | Position	224	91
Federal Agency [Member]
Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	$ 9,949
12 months or longer	0
Total	9,949
Unrealized Loss Position, Unrealized Losses [Abstract]
Less than 12 months	(46)
12 months or longer	0
Total	$ (46)
Unrealized Loss Position, Number of Positions [Abstract]
Less than 12 months | Position	2
12 months or longer | Position	0
Total | Position	2
Mortgage-Backed [Member]
Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	$ 55,712	$ 15,477
12 months or longer	42,778	33,703
Total	98,490	49,180
Unrealized Loss Position, Unrealized Losses [Abstract]
Less than 12 months	(1,678)	(140)
12 months or longer	(2,466)	(670)
Total	$ (4,144)	$ (810)
Unrealized Loss Position, Number of Positions [Abstract]
Less than 12 months | Position	5	2
12 months or longer | Position	4	2
Total | Position	9	4
Collateralized Mortgage Obligations [Member]
Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	$ 153,768	$ 118,476
12 months or longer	97,515	37,614
Total	251,283	156,090
Unrealized Loss Position, Unrealized Losses [Abstract]
Less than 12 months	(2,195)	(1,064)
12 months or longer	(4,952)	(1,513)
Total	$ (7,147)	$ (2,577)
Unrealized Loss Position, Number of Positions [Abstract]
Less than 12 months | Position	22	17
12 months or longer | Position	16	6
Total | Position	38	23
State & Municipal [Member]
Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	$ 84,258	$ 22,387
12 months or longer	27,384	15,720
Total	111,642	38,107
Unrealized Loss Position, Unrealized Losses [Abstract]
Less than 12 months	(1,276)	(132)
12 months or longer	(1,765)	(488)
Total	$ (3,041)	$ (620)
Unrealized Loss Position, Number of Positions [Abstract]
Less than 12 months | Position	134	40
12 months or longer | Position	41	24
Total | Position	175	64

Securities, Unrealized Gains (L

Securities, Unrealized Gains (Losses) Related to Equity Securities (Details) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2018USD ($)Issuer	Sep. 30, 2018USD ($)Issuer	Dec. 31, 2017Issuer
Gains and losses on equity securities [Abstract]
Net gains and losses recognized on equity securities	$ 412	$ 575
Less: Net gains and losses recognized during the period on equity securities sold during the period	511	555
Unrealized gains and losses recognized on equity securities still held	(99)	20
Carrying amount of equity securities without readily determinable fair values	4,000	4,000
Impairment adjustments of equity securities without readily determinable fair values	0	0
Downward adjustments of equity securities without readily determinable fair values	0	0
Upward adjustments of equity securities without readily determinable fair values	$ 0	$ 0
Number of issuers whose holdings exceeded 10% of consolidated stockholders' equity, excluding U.S. Government securities | Issuer	0	0	0

Securities, AFS Debt Securities

Securities, AFS Debt Securities, Contractual Maturities (Details) $ in Thousands	Sep. 30, 2018USD ($)
Available-for-sale Securities, Debt Maturities, Amortized Cost [Abstract]
Within one year	$ 46,641
From one to five years	86,348
From five to ten years	176,260
After ten years	832,196
Amortized cost	1,141,445
Available-for-sale Securities, Debt Maturities, Estimated Fair Value [Abstract]
Within one year	46,521
From one to five years	84,188
From five to ten years	171,240
After ten years	799,125
Fair value	$ 1,101,074

Securities, HTM Debt Securities

Securities, HTM Debt Securities, Contractual Maturities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Held-to-maturity Securities, Debt Maturities, Amortized Cost [Abstract]
Within one year	$ 89,011
From one to five years	53,217
From five to ten years	215,931
After ten years	301,790
Amortized cost	659,949	$ 484,073
Held-to-maturity Securities, Debt Maturities, Estimated Fair Value [Abstract]
Within one year	89,011
From one to five years	53,177
From five to ten years	209,974
After ten years	293,570
Fair value	$ 645,732	$ 481,871

Allowance for Loan Losses and_4

Allowance for Loan Losses and Credit Quality of Loans (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2018USD ($)Segment	Mar. 31, 2018
Allowance for Loan Losses [Abstract]
Loan portfolio segments | Segment	3
Agricultural [Member] | Maximum [Member]
Allowance for Loan Losses [Abstract]
Loan amount, percentage of commercial portfolio		3.00%
Specialty Lending [Member]
Allowance for Loan Losses [Abstract]
Loan amount, percentage of consumer portfolio		21.00%
Commercial Loans [Member] | Commercial Real Estate [Member] | Maximum [Member]
Allowance for Loan Losses [Abstract]
Loan amount, percentage of appraised value or purchase price of the property	80.00%
Commercial Loans [Member] | Agricultural Real Estate [Member] | Maximum [Member]
Allowance for Loan Losses [Abstract]
Loan amount, percentage of appraised value or purchase price of the property	75.00%
Commercial Loans [Member] | Business Banking [Member] | Maximum [Member]
Allowance for Loan Losses [Abstract]
Business banking loans, amount available | $	$ 750
Consumer Loans [Member] | Dealer Finance [Member]
Allowance for Loan Losses [Abstract]
Percentage of automobile financing to indirect relationships with dealers	95.00%
Consumer Loans [Member] | Dealer Finance [Member] | Minimum [Member]
Allowance for Loan Losses [Abstract]
Principal repayment term of loan	3 years
Consumer Loans [Member] | Dealer Finance [Member] | Maximum [Member]
Allowance for Loan Losses [Abstract]
Principal repayment term of loan	6 years
Consumer Loans [Member] | Direct [Member] | Minimum [Member]
Allowance for Loan Losses [Abstract]
Principal repayment term of loan	1 year
Consumer Loans [Member] | Direct [Member] | Maximum [Member]
Allowance for Loan Losses [Abstract]
Principal repayment term of loan	10 years
Consumer Loans [Member] | Home Equity [Member] | Maximum [Member]
Allowance for Loan Losses [Abstract]
Loan amount, percentage of appraised value or purchase price of the property	85.00%
Loan amount, percentage of equity in property	85.00%
Residential Real Estate [Member] | Maximum [Member]
Allowance for Loan Losses [Abstract]
Loan amount, percentage of appraised value or purchase price of the property	85.00%

Allowance for Loan Losses and_5

Allowance for Loan Losses and Credit Quality of Loans, Allowance for Loan Losses by Portfolio Segments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Changes in allowance for loan losses by portfolio segment [Roll Forward]
Balance, beginning of period	$ 72,450	$ 66,600	$ 69,500	$ 65,200
Charge-offs	(7,764)	(7,974)	(24,995)	(24,450)
Recoveries	2,093	1,835	6,000	4,765
Provision	6,026	7,889	22,300	22,835
Balance, end of period	72,805	68,350	72,805	68,350
Commercial Loans [Member]
Changes in allowance for loan losses by portfolio segment [Roll Forward]
Balance, beginning of period	31,059	24,428	27,606	25,444
Charge-offs	(823)	(574)	(2,535)	(2,991)
Recoveries	410	266	780	919
Provision	1,086	1,434	5,881	2,182
Balance, end of period	31,732	25,554	31,732	25,554
Consumer Loans [Member]
Changes in allowance for loan losses by portfolio segment [Roll Forward]
Balance, beginning of period	36,479	35,523	36,830	33,375
Charge-offs	(6,818)	(6,979)	(21,947)	(19,742)
Recoveries	1,602	1,446	4,946	3,680
Provision	6,044	6,197	17,478	18,874
Balance, end of period	37,307	36,187	37,307	36,187
Residential Real Estate [Member]
Changes in allowance for loan losses by portfolio segment [Roll Forward]
Balance, beginning of period	4,912	6,649	5,064	6,381
Charge-offs	(123)	(421)	(513)	(1,717)
Recoveries	81	123	274	166
Provision	(1,104)	258	(1,059)	1,779
Balance, end of period	3,766	6,609	3,766	6,609
Acquired Loans [Member]
Changes in allowance for loan losses by portfolio segment [Roll Forward]
Balance, beginning of period			0
Charge-offs	0	$ 0	100	$ 700
Balance, end of period	$ 0		$ 0

Allowance for Loan Losses and_6

Allowance for Loan Losses and Credit Quality of Loans, Allowance for Loan Losses and Recorded Investment in Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Allowance for loan losses	$ 72,805	$ 72,450	$ 69,500	$ 68,350	$ 66,600	$ 65,200
Allowance for loans individually evaluated for impairment	25		57
Allowance for loans collectively evaluated for impairment	72,780		69,443
Ending balance of loans	6,887,262		6,583,639
Commercial Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Allowance for loan losses	31,732	31,059	27,606	25,554	24,428	25,444
Allowance for loans individually evaluated for impairment	25		57
Allowance for loans collectively evaluated for impairment	31,707		27,549
Ending balance of loans	3,212,577		3,028,269
Consumer Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Allowance for loan losses	37,307	36,479	36,830	36,187	35,523	33,375
Allowance for loans individually evaluated for impairment	0		0
Allowance for loans collectively evaluated for impairment	37,307		36,830
Ending balance of loans	2,301,198		2,234,349
Residential Real Estate [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Allowance for loan losses	3,766	$ 4,912	5,064	$ 6,609	$ 6,649	$ 6,381
Allowance for loans individually evaluated for impairment	0		0
Allowance for loans collectively evaluated for impairment	3,766		5,064
Ending balance of loans	1,373,487		1,321,021
Originated Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	6,546,387		6,181,948
Ending balance of loans individually evaluated for impairment	19,282		21,138
Ending balance of loans collectively evaluated for impairment	6,527,105		6,160,810
Originated Loans [Member] | Commercial Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	3,058,769		2,840,956
Ending balance of loans individually evaluated for impairment	5,077		5,876
Ending balance of loans collectively evaluated for impairment	3,053,692		2,835,080
Originated Loans [Member] | Consumer Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	2,267,204		2,190,443
Ending balance of loans individually evaluated for impairment	7,760		8,432
Ending balance of loans collectively evaluated for impairment	2,259,444		2,182,011
Originated Loans [Member] | Residential Real Estate [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	1,220,414		1,150,549
Ending balance of loans individually evaluated for impairment	6,445		6,830
Ending balance of loans collectively evaluated for impairment	1,213,969		1,143,719
Acquired Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Allowance for loan losses	0		0
Ending balance of loans	340,875		401,691
Ending balance of loans collectively evaluated for impairment	340,875		401,691
Acquired Loans [Member] | Commercial Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	153,808		187,313
Ending balance of loans collectively evaluated for impairment	153,808		187,313
Acquired Loans [Member] | Consumer Loans [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	33,994		43,906
Ending balance of loans collectively evaluated for impairment	33,994		43,906
Acquired Loans [Member] | Residential Real Estate [Member]
Allowance for loan losses and recorded investment by portfolio segment [Abstract]
Ending balance of loans	153,073		170,472
Ending balance of loans collectively evaluated for impairment	$ 153,073		$ 170,472

Allowance for Loan Losses and_7

Allowance for Loan Losses and Credit Quality of Loans, Past Due Loans (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment, Aging [Abstract]
Minimum number of days past due for nonaccrual loan status	90 days
Total past due accruing	$ 36,519	$ 41,730
Nonaccrual	23,301	25,708
Current	6,827,442	6,516,201
Recorded total loans	6,887,262	6,583,639
31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	26,231	29,662
61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	5,554	6,658
Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	4,734	5,410
Commercial Loans [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded total loans	3,212,577	3,028,269
Consumer Loans [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded total loans	2,301,198	2,234,349
Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded total loans	1,373,487	1,321,021
Originated Loans [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	34,702	39,945
Nonaccrual	21,008	23,336
Current	6,490,677	6,118,667
Recorded total loans	6,546,387	6,181,948
Originated Loans [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	24,740	28,383
Originated Loans [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	5,501	6,397
Originated Loans [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	4,461	5,165
Originated Loans [Member] | Commercial Loans [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	2,799	3,413
Nonaccrual	10,299	12,463
Current	3,045,671	2,825,080
Recorded total loans	3,058,769	2,840,956
Originated Loans [Member] | Commercial Loans [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	2,660	2,678
Originated Loans [Member] | Commercial Loans [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	139	735
Originated Loans [Member] | Commercial Loans [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	0	0
Originated Loans [Member] | Commercial Loans [Member] | C&I [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	250
Nonaccrual	908
Current	857,782
Recorded total loans	858,940
Originated Loans [Member] | Commercial Loans [Member] | C&I [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	209
Originated Loans [Member] | Commercial Loans [Member] | C&I [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	41
Originated Loans [Member] | Commercial Loans [Member] | C&I [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	0
Originated Loans [Member] | Commercial Loans [Member] | CRE [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	1,133
Nonaccrual	3,637
Current	1,708,369
Recorded total loans	1,713,139
Originated Loans [Member] | Commercial Loans [Member] | CRE [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	1,133
Originated Loans [Member] | Commercial Loans [Member] | CRE [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	0
Originated Loans [Member] | Commercial Loans [Member] | CRE [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	0
Originated Loans [Member] | Commercial Loans [Member] | Commercial [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		0
Nonaccrual		202
Current		753,577
Recorded total loans		753,779
Originated Loans [Member] | Commercial Loans [Member] | Commercial [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		0
Originated Loans [Member] | Commercial Loans [Member] | Commercial [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		0
Originated Loans [Member] | Commercial Loans [Member] | Commercial [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		0
Originated Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		299
Nonaccrual		3,178
Current		1,533,065
Recorded total loans		1,536,542
Originated Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		161
Originated Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		138
Originated Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		0
Originated Loans [Member] | Commercial Loans [Member] | Agricultural [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		117
Nonaccrual		1,043
Current		34,386
Recorded total loans		35,546
Originated Loans [Member] | Commercial Loans [Member] | Agricultural [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		117
Originated Loans [Member] | Commercial Loans [Member] | Agricultural [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		0
Originated Loans [Member] | Commercial Loans [Member] | Agricultural [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		0
Originated Loans [Member] | Commercial Loans [Member] | Agricultural Real Estate [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		493
Nonaccrual		2,736
Current		30,905
Recorded total loans		34,134
Originated Loans [Member] | Commercial Loans [Member] | Agricultural Real Estate [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		493
Originated Loans [Member] | Commercial Loans [Member] | Agricultural Real Estate [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		0
Originated Loans [Member] | Commercial Loans [Member] | Agricultural Real Estate [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		0
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	1,416	2,504
Nonaccrual	5,754	5,304
Current	479,520	473,147
Recorded total loans	486,690	480,955
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	1,318	1,907
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	98	597
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	0	0
Originated Loans [Member] | Consumer Loans [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	29,087	30,873
Nonaccrual	4,603	4,886
Current	2,233,514	2,154,684
Recorded total loans	2,267,204	2,190,443
Originated Loans [Member] | Consumer Loans [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	20,714	21,975
Originated Loans [Member] | Consumer Loans [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	5,143	4,995
Originated Loans [Member] | Consumer Loans [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	3,230	3,903
Originated Loans [Member] | Consumer Loans [Member] | Indirect [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		26,272
Nonaccrual		2,115
Current		1,642,204
Recorded total loans		1,670,591
Originated Loans [Member] | Consumer Loans [Member] | Indirect [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		18,747
Originated Loans [Member] | Consumer Loans [Member] | Indirect [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		4,033
Originated Loans [Member] | Consumer Loans [Member] | Indirect [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		3,492
Originated Loans [Member] | Consumer Loans [Member] | Dealer Finance [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	17,655
Nonaccrual	2,062
Current	1,209,880
Recorded total loans	1,229,597
Originated Loans [Member] | Consumer Loans [Member] | Dealer Finance [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	14,364
Originated Loans [Member] | Consumer Loans [Member] | Dealer Finance [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	2,039
Originated Loans [Member] | Consumer Loans [Member] | Dealer Finance [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	1,252
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	4,696
Nonaccrual	2,541
Current	508,974
Recorded total loans	516,211
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	3,313
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	949
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	434
Originated Loans [Member] | Consumer Loans [Member] | Specialty Lending [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	6,736
Nonaccrual	0
Current	514,660
Recorded total loans	521,396
Originated Loans [Member] | Consumer Loans [Member] | Specialty Lending [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	3,037
Originated Loans [Member] | Consumer Loans [Member] | Specialty Lending [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	2,155
Originated Loans [Member] | Consumer Loans [Member] | Specialty Lending [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	1,544
Originated Loans [Member] | Consumer Loans [Member] | Home Equity [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		4,082
Nonaccrual		2,736
Current		448,081
Recorded total loans		454,899
Originated Loans [Member] | Consumer Loans [Member] | Home Equity [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		2,887
Originated Loans [Member] | Consumer Loans [Member] | Home Equity [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		854
Originated Loans [Member] | Consumer Loans [Member] | Home Equity [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		341
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		519
Nonaccrual		35
Current		64,399
Recorded total loans		64,953
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		341
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		108
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		70
Originated Loans [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	2,816	5,659
Nonaccrual	6,106	5,987
Current	1,211,492	1,138,903
Recorded total loans	1,220,414	1,150,549
Originated Loans [Member] | Residential Real Estate [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	1,366	3,730
Originated Loans [Member] | Residential Real Estate [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	219	667
Originated Loans [Member] | Residential Real Estate [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	1,231	1,262
Acquired Loans [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	1,817	1,785
Nonaccrual	2,293	2,372
Current	336,765	397,534
Recorded total loans	340,875	401,691
Acquired Loans [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	1,491	1,279
Acquired Loans [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	53	261
Acquired Loans [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	273	245
Acquired Loans [Member] | Commercial Loans [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	665	354
Nonaccrual	613	671
Current	152,530	186,288
Recorded total loans	153,808	187,313
Acquired Loans [Member] | Commercial Loans [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	425	354
Acquired Loans [Member] | Commercial Loans [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	0	0
Acquired Loans [Member] | Commercial Loans [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	240	0
Acquired Loans [Member] | Commercial Loans [Member] | C&I [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	0
Nonaccrual	0
Current	30,871
Recorded total loans	30,871
Acquired Loans [Member] | Commercial Loans [Member] | C&I [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	0
Acquired Loans [Member] | Commercial Loans [Member] | C&I [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	0
Acquired Loans [Member] | Commercial Loans [Member] | C&I [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	0
Acquired Loans [Member] | Commercial Loans [Member] | CRE [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	0
Nonaccrual	2
Current	87,827
Recorded total loans	87,829
Acquired Loans [Member] | Commercial Loans [Member] | CRE [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	0
Acquired Loans [Member] | Commercial Loans [Member] | CRE [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	0
Acquired Loans [Member] | Commercial Loans [Member] | CRE [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	0
Acquired Loans [Member] | Commercial Loans [Member] | Commercial [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		0
Nonaccrual		0
Current		39,575
Recorded total loans		39,575
Acquired Loans [Member] | Commercial Loans [Member] | Commercial [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		0
Acquired Loans [Member] | Commercial Loans [Member] | Commercial [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		0
Acquired Loans [Member] | Commercial Loans [Member] | Commercial [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		0
Acquired Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		0
Nonaccrual		2
Current		106,632
Recorded total loans		106,634
Acquired Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		0
Acquired Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		0
Acquired Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		0
Acquired Loans [Member] | Commercial Loans [Member] | Business Banking [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	665	354
Nonaccrual	611	669
Current	33,832	40,081
Recorded total loans	35,108	41,104
Acquired Loans [Member] | Commercial Loans [Member] | Business Banking [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	425	354
Acquired Loans [Member] | Commercial Loans [Member] | Business Banking [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	0	0
Acquired Loans [Member] | Commercial Loans [Member] | Business Banking [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	240	0
Acquired Loans [Member] | Consumer Loans [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	241	438
Nonaccrual	275	270
Current	33,478	43,198
Recorded total loans	33,994	43,906
Acquired Loans [Member] | Consumer Loans [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	227	298
Acquired Loans [Member] | Consumer Loans [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	14	35
Acquired Loans [Member] | Consumer Loans [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	0	105
Acquired Loans [Member] | Consumer Loans [Member] | Indirect [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		39
Nonaccrual		22
Current		1,157
Recorded total loans		1,218
Acquired Loans [Member] | Consumer Loans [Member] | Indirect [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		38
Acquired Loans [Member] | Consumer Loans [Member] | Indirect [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		0
Acquired Loans [Member] | Consumer Loans [Member] | Indirect [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		1
Acquired Loans [Member] | Consumer Loans [Member] | Dealer Finance [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	4
Nonaccrual	0
Current	99
Recorded total loans	103
Acquired Loans [Member] | Consumer Loans [Member] | Dealer Finance [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	4
Acquired Loans [Member] | Consumer Loans [Member] | Dealer Finance [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	0
Acquired Loans [Member] | Consumer Loans [Member] | Dealer Finance [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	0
Acquired Loans [Member] | Consumer Loans [Member] | Direct [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	237	8
Nonaccrual	275	23
Current	33,379	2,785
Recorded total loans	33,891	2,816
Acquired Loans [Member] | Consumer Loans [Member] | Direct [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	223	6
Acquired Loans [Member] | Consumer Loans [Member] | Direct [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	14	1
Acquired Loans [Member] | Consumer Loans [Member] | Direct [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	0	1
Acquired Loans [Member] | Consumer Loans [Member] | Home Equity [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		391
Nonaccrual		225
Current		39,256
Recorded total loans		39,872
Acquired Loans [Member] | Consumer Loans [Member] | Home Equity [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		254
Acquired Loans [Member] | Consumer Loans [Member] | Home Equity [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		34
Acquired Loans [Member] | Consumer Loans [Member] | Home Equity [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing		103
Acquired Loans [Member] | Consumer Loans [Member] | Direct [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Recorded total loans		2,816
Acquired Loans [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	911	993
Nonaccrual	1,405	1,431
Current	150,757	168,048
Recorded total loans	153,073	170,472
Acquired Loans [Member] | Residential Real Estate [Member] | 31-60 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	839	627
Acquired Loans [Member] | Residential Real Estate [Member] | 61-90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	39	226
Acquired Loans [Member] | Residential Real Estate [Member] | Greater Than 90 Days Past Due Accruing [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total past due accruing	$ 33	$ 140

Allowance for Loan Losses and_8

Allowance for Loan Losses and Credit Quality of Loans, Impaired Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Allowance for Loan Losses and Credit Quality of Loans [Abstract]
Threshold balance for classified loans to be evaluated individually for impairment	$ 750
Total Loans [Abstract]
Recorded investment balance (book)	19,282	$ 21,138
Unpaid principal balance (legal)	26,991	28,120
Related allowance	25	57
Acquired impaired loans specifically evaluated for impairment	0	0
Originated Loans [Member]
With an allowance recorded [Abstract]
Recorded investment balance (book)	19,257	21,035
Unpaid principal balance (legal)	26,966	28,011
Originated Loans [Member] | Commercial Loans [Member]
With no related allowance recorded [Abstract]
Recorded investment balance (book)	5,052	5,773
Unpaid principal balance (legal)	8,391	8,848
With an allowance recorded [Abstract]
Recorded investment balance (book)	25	103
Unpaid principal balance (legal)	25	109
Total Loans [Abstract]
Related allowance	25	57
Originated Loans [Member] | Commercial Loans [Member] | C&I [Member]
With no related allowance recorded [Abstract]
Recorded investment balance (book)	404
Unpaid principal balance (legal)	676
With an allowance recorded [Abstract]
Recorded investment balance (book)	25
Unpaid principal balance (legal)	25
Total Loans [Abstract]
Related allowance	25
Originated Loans [Member] | Commercial Loans [Member] | CRE [Member]
With no related allowance recorded [Abstract]
Recorded investment balance (book)	3,629
Unpaid principal balance (legal)	5,616
Originated Loans [Member] | Commercial Loans [Member] | Commercial [Member]
With no related allowance recorded [Abstract]
Recorded investment balance (book)		0
Unpaid principal balance (legal)		251
Originated Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member]
With no related allowance recorded [Abstract]
Recorded investment balance (book)		2,211
Unpaid principal balance (legal)		3,979
With an allowance recorded [Abstract]
Recorded investment balance (book)		76
Unpaid principal balance (legal)		82
Total Loans [Abstract]
Related allowance		30
Originated Loans [Member] | Commercial Loans [Member] | Agricultural [Member]
With no related allowance recorded [Abstract]
Recorded investment balance (book)		452
Unpaid principal balance (legal)		465
With an allowance recorded [Abstract]
Recorded investment balance (book)		27
Unpaid principal balance (legal)		27
Total Loans [Abstract]
Related allowance		27
Originated Loans [Member] | Commercial Loans [Member] | Agricultural Real Estate [Member]
With no related allowance recorded [Abstract]
Recorded investment balance (book)		2,250
Unpaid principal balance (legal)		2,423
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member]
With no related allowance recorded [Abstract]
Recorded investment balance (book)	1,019	860
Unpaid principal balance (legal)	2,099	1,730
Originated Loans [Member] | Consumer Loans [Member]
With no related allowance recorded [Abstract]
Recorded investment balance (book)	7,760	8,432
Unpaid principal balance (legal)	9,854	10,383
Originated Loans [Member] | Consumer Loans [Member] | Dealer Finance [Member]
With no related allowance recorded [Abstract]
Recorded investment balance (book)	160
Unpaid principal balance (legal)	254
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member]
With no related allowance recorded [Abstract]
Recorded investment balance (book)	7,600
Unpaid principal balance (legal)	9,600
Originated Loans [Member] | Consumer Loans [Member] | Indirect [Member]
With no related allowance recorded [Abstract]
Recorded investment balance (book)		131
Unpaid principal balance (legal)		143
Originated Loans [Member] | Consumer Loans [Member] | Home Equity [Member]
With no related allowance recorded [Abstract]
Recorded investment balance (book)		8,027
Unpaid principal balance (legal)		9,966
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member]
With no related allowance recorded [Abstract]
Recorded investment balance (book)		274
Unpaid principal balance (legal)		274
Originated Loans [Member] | Residential Real Estate [Member]
With an allowance recorded [Abstract]
Recorded investment balance (book)	6,445	6,830
Unpaid principal balance (legal)	$ 8,721	$ 8,780

Allowance for Loan Losses and_9

Allowance for Loan Losses and Credit Quality of Loans, Average Recorded Investments on Loans Specifically Evaluated for Impairment and Interest Income Recognized (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	$ 19,528	$ 20,936	$ 20,305	$ 23,789
Interest income recognized	210	257	646	679
Originated Loans [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	19,528	20,936	20,305	23,668
Interest income recognized	210	257	646	679
Originated Loans [Member] | Commercial Loans [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	5,102	5,990	5,446	8,828
Interest income recognized	36	61	109	133
Originated Loans [Member] | Commercial Loans [Member] | C&I [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	433		449
Interest income recognized	0		1
Originated Loans [Member] | Commercial Loans [Member] | CRE [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	3,645		3,999
Interest income recognized	32		96
Originated Loans [Member] | Commercial Loans [Member] | Commercial [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment		1,000		2,393
Interest income recognized		0		0
Originated Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment		2,415		3,906
Interest income recognized		48		93
Originated Loans [Member] | Commercial Loans [Member] | Agricultural [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment		115		147
Interest income recognized		0		1
Originated Loans [Member] | Commercial Loans [Member] | Agricultural Real Estate [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment		1,505		1,545
Interest income recognized		11		32
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	1,024	955	998	837
Interest income recognized	4	2	12	7
Originated Loans [Member] | Consumer Loans [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	7,907	8,313	8,140	8,415
Interest income recognized	106	114	325	335
Originated Loans [Member] | Consumer Loans [Member] | Dealer Finance [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	177		187
Interest income recognized	4		8
Originated Loans [Member] | Consumer Loans [Member] | Direct Lending [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	7,730		7,953
Interest income recognized	102		317
Originated Loans [Member] | Consumer Loans [Member] | Indirect [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment		35		22
Interest income recognized		1		2
Originated Loans [Member] | Consumer Loans [Member] | Home Equity [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment		8,159		8,274
Interest income recognized		111		331
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment		119		119
Interest income recognized		2		2
Originated Loans [Member] | Residential Real Estate [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	6,519	6,633	6,719	6,425
Interest income recognized	$ 68	$ 82	212	211
Acquired Loans [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment			0	121
Interest income recognized			0	0
Acquired Loans [Member] | Commercial Loans [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment			0	121
Interest income recognized			0	0
Acquired Loans [Member] | Commercial Loans [Member] | Commercial Real Estate [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment			0	121
Interest income recognized			$ 0	$ 0

Allowance for Loan Losses an_10

Allowance for Loan Losses and Credit Quality of Loans, Credit Quality by Loan Class (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Credit Quality by Loan Class [Abstract]
Net loans	$ 6,887,262	$ 6,583,639
Consumer Credit Exposure [Member]
Credit Quality by Loan Class [Abstract]
Net loans	2,301,198	2,234,349
Residential Real Estate Mortgage Credit Exposure [Member]
Credit Quality by Loan Class [Abstract]
Net loans	1,373,487	1,321,021
Originated Loans [Member]
Credit Quality by Loan Class [Abstract]
Net loans	6,546,387	6,181,948
Originated Loans [Member] | Commercial Credit Exposure [Member] | Total Commercial, Industrial and Commercial Real Estate [Member]
Credit Quality by Loan Class [Abstract]
Net loans	2,572,079
Originated Loans [Member] | Commercial Credit Exposure [Member] | Total Commercial, Industrial and Commercial Real Estate [Member] | Pass [Member]
Credit Quality by Loan Class [Abstract]
Net loans	2,466,233
Originated Loans [Member] | Commercial Credit Exposure [Member] | Total Commercial, Industrial and Commercial Real Estate [Member] | Special Mention [Member]
Credit Quality by Loan Class [Abstract]
Net loans	50,319
Originated Loans [Member] | Commercial Credit Exposure [Member] | Total Commercial, Industrial and Commercial Real Estate [Member] | Substandard [Member]
Credit Quality by Loan Class [Abstract]
Net loans	55,527
Originated Loans [Member] | Commercial Credit Exposure [Member] | C&I [Member]
Credit Quality by Loan Class [Abstract]
Net loans	858,940
Originated Loans [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Pass [Member]
Credit Quality by Loan Class [Abstract]
Net loans	805,333
Originated Loans [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Special Mention [Member]
Credit Quality by Loan Class [Abstract]
Net loans	33,557
Originated Loans [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Substandard [Member]
Credit Quality by Loan Class [Abstract]
Net loans	20,050
Originated Loans [Member] | Commercial Credit Exposure [Member] | CRE [Member]
Credit Quality by Loan Class [Abstract]
Net loans	1,713,139
Originated Loans [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Pass [Member]
Credit Quality by Loan Class [Abstract]
Net loans	1,660,900
Originated Loans [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Special Mention [Member]
Credit Quality by Loan Class [Abstract]
Net loans	16,762
Originated Loans [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Substandard [Member]
Credit Quality by Loan Class [Abstract]
Net loans	35,477
Originated Loans [Member] | Commercial Credit Exposure [Member] | Total Commercial and Agricultural [Member]
Credit Quality by Loan Class [Abstract]
Net loans		2,360,001
Originated Loans [Member] | Commercial Credit Exposure [Member] | Total Commercial and Agricultural [Member] | Pass [Member]
Credit Quality by Loan Class [Abstract]
Net loans		2,245,016
Originated Loans [Member] | Commercial Credit Exposure [Member] | Total Commercial and Agricultural [Member] | Special Mention [Member]
Credit Quality by Loan Class [Abstract]
Net loans		63,336
Originated Loans [Member] | Commercial Credit Exposure [Member] | Total Commercial and Agricultural [Member] | Substandard [Member]
Credit Quality by Loan Class [Abstract]
Net loans		51,649
Originated Loans [Member] | Commercial Credit Exposure [Member] | Commercial [Member]
Credit Quality by Loan Class [Abstract]
Net loans		753,779
Originated Loans [Member] | Commercial Credit Exposure [Member] | Commercial [Member] | Pass [Member]
Credit Quality by Loan Class [Abstract]
Net loans		708,567
Originated Loans [Member] | Commercial Credit Exposure [Member] | Commercial [Member] | Special Mention [Member]
Credit Quality by Loan Class [Abstract]
Net loans		30,337
Originated Loans [Member] | Commercial Credit Exposure [Member] | Commercial [Member] | Substandard [Member]
Credit Quality by Loan Class [Abstract]
Net loans		14,875
Originated Loans [Member] | Commercial Credit Exposure [Member] | Commercial Real Estate [Member]
Credit Quality by Loan Class [Abstract]
Net loans		1,536,542
Originated Loans [Member] | Commercial Credit Exposure [Member] | Commercial Real Estate [Member] | Pass [Member]
Credit Quality by Loan Class [Abstract]
Net loans		1,481,926
Originated Loans [Member] | Commercial Credit Exposure [Member] | Commercial Real Estate [Member] | Special Mention [Member]
Credit Quality by Loan Class [Abstract]
Net loans		28,264
Originated Loans [Member] | Commercial Credit Exposure [Member] | Commercial Real Estate [Member] | Substandard [Member]
Credit Quality by Loan Class [Abstract]
Net loans		26,352
Originated Loans [Member] | Commercial Credit Exposure [Member] | Agricultural [Member]
Credit Quality by Loan Class [Abstract]
Net loans		35,546
Originated Loans [Member] | Commercial Credit Exposure [Member] | Agricultural [Member] | Pass [Member]
Credit Quality by Loan Class [Abstract]
Net loans		31,142
Originated Loans [Member] | Commercial Credit Exposure [Member] | Agricultural [Member] | Special Mention [Member]
Credit Quality by Loan Class [Abstract]
Net loans		2,294
Originated Loans [Member] | Commercial Credit Exposure [Member] | Agricultural [Member] | Substandard [Member]
Credit Quality by Loan Class [Abstract]
Net loans		2,110
Originated Loans [Member] | Commercial Credit Exposure [Member] | Agricultural Real Estate [Member]
Credit Quality by Loan Class [Abstract]
Net loans		34,134
Originated Loans [Member] | Commercial Credit Exposure [Member] | Agricultural Real Estate [Member] | Pass [Member]
Credit Quality by Loan Class [Abstract]
Net loans		23,381
Originated Loans [Member] | Commercial Credit Exposure [Member] | Agricultural Real Estate [Member] | Special Mention [Member]
Credit Quality by Loan Class [Abstract]
Net loans		2,441
Originated Loans [Member] | Commercial Credit Exposure [Member] | Agricultural Real Estate [Member] | Substandard [Member]
Credit Quality by Loan Class [Abstract]
Net loans		8,312
Originated Loans [Member] | Business Banking Credit Exposure [Member]
Credit Quality by Loan Class [Abstract]
Net loans	486,690	480,955
Originated Loans [Member] | Business Banking Credit Exposure [Member] | Non-classified [Member]
Credit Quality by Loan Class [Abstract]
Net loans	474,252	468,898
Originated Loans [Member] | Business Banking Credit Exposure [Member] | Classified [Member]
Credit Quality by Loan Class [Abstract]
Net loans	12,438	12,057
Originated Loans [Member] | Business Banking Credit Exposure [Member] | Business Banking [Member]
Credit Quality by Loan Class [Abstract]
Net loans	486,690	480,955
Originated Loans [Member] | Business Banking Credit Exposure [Member] | Business Banking [Member] | Non-classified [Member]
Credit Quality by Loan Class [Abstract]
Net loans	474,252	468,898
Originated Loans [Member] | Business Banking Credit Exposure [Member] | Business Banking [Member] | Classified [Member]
Credit Quality by Loan Class [Abstract]
Net loans	12,438	12,057
Originated Loans [Member] | Consumer Credit Exposure [Member]
Credit Quality by Loan Class [Abstract]
Net loans	2,267,204	2,190,443
Originated Loans [Member] | Consumer Credit Exposure [Member] | Performing [Member]
Credit Quality by Loan Class [Abstract]
Net loans	2,259,371	2,181,654
Originated Loans [Member] | Consumer Credit Exposure [Member] | Nonperforming [Member]
Credit Quality by Loan Class [Abstract]
Net loans	7,833	8,789
Originated Loans [Member] | Consumer Credit Exposure [Member] | Dealer Finance [Member]
Credit Quality by Loan Class [Abstract]
Net loans	1,229,597
Originated Loans [Member] | Consumer Credit Exposure [Member] | Dealer Finance [Member] | Performing [Member]
Credit Quality by Loan Class [Abstract]
Net loans	1,226,283
Originated Loans [Member] | Consumer Credit Exposure [Member] | Dealer Finance [Member] | Nonperforming [Member]
Credit Quality by Loan Class [Abstract]
Net loans	3,314
Originated Loans [Member] | Consumer Credit Exposure [Member] | Direct [Member]
Credit Quality by Loan Class [Abstract]
Net loans	516,211
Originated Loans [Member] | Consumer Credit Exposure [Member] | Direct [Member] | Performing [Member]
Credit Quality by Loan Class [Abstract]
Net loans	513,236
Originated Loans [Member] | Consumer Credit Exposure [Member] | Direct [Member] | Nonperforming [Member]
Credit Quality by Loan Class [Abstract]
Net loans	2,975
Originated Loans [Member] | Consumer Credit Exposure [Member] | Specialty Lending [Member]
Credit Quality by Loan Class [Abstract]
Net loans	521,396
Originated Loans [Member] | Consumer Credit Exposure [Member] | Specialty Lending [Member] | Performing [Member]
Credit Quality by Loan Class [Abstract]
Net loans	519,852
Originated Loans [Member] | Consumer Credit Exposure [Member] | Specialty Lending [Member] | Nonperforming [Member]
Credit Quality by Loan Class [Abstract]
Net loans	1,544
Originated Loans [Member] | Consumer Credit Exposure [Member] | Indirect [Member]
Credit Quality by Loan Class [Abstract]
Net loans		1,670,591
Originated Loans [Member] | Consumer Credit Exposure [Member] | Indirect [Member] | Performing [Member]
Credit Quality by Loan Class [Abstract]
Net loans		1,664,984
Originated Loans [Member] | Consumer Credit Exposure [Member] | Indirect [Member] | Nonperforming [Member]
Credit Quality by Loan Class [Abstract]
Net loans		5,607
Originated Loans [Member] | Consumer Credit Exposure [Member] | Home Equity [Member]
Credit Quality by Loan Class [Abstract]
Net loans		454,899
Originated Loans [Member] | Consumer Credit Exposure [Member] | Home Equity [Member] | Performing [Member]
Credit Quality by Loan Class [Abstract]
Net loans		451,822
Originated Loans [Member] | Consumer Credit Exposure [Member] | Home Equity [Member] | Nonperforming [Member]
Credit Quality by Loan Class [Abstract]
Net loans		3,077
Originated Loans [Member] | Consumer Credit Exposure [Member] | Direct [Member]
Credit Quality by Loan Class [Abstract]
Net loans		64,953
Originated Loans [Member] | Consumer Credit Exposure [Member] | Direct [Member] | Performing [Member]
Credit Quality by Loan Class [Abstract]
Net loans		64,848
Originated Loans [Member] | Consumer Credit Exposure [Member] | Direct [Member] | Nonperforming [Member]
Credit Quality by Loan Class [Abstract]
Net loans		105
Originated Loans [Member] | Residential Real Estate Mortgage Credit Exposure [Member]
Credit Quality by Loan Class [Abstract]
Net loans	1,220,414	1,150,549
Originated Loans [Member] | Residential Real Estate Mortgage Credit Exposure [Member] | Performing [Member]
Credit Quality by Loan Class [Abstract]
Net loans	1,213,077	1,143,300
Originated Loans [Member] | Residential Real Estate Mortgage Credit Exposure [Member] | Nonperforming [Member]
Credit Quality by Loan Class [Abstract]
Net loans	7,337	7,249
Originated Loans [Member] | Residential Real Estate Mortgage Credit Exposure [Member] | Residential Real Estate Mortgage [Member]
Credit Quality by Loan Class [Abstract]
Net loans	1,220,414	1,150,549
Originated Loans [Member] | Residential Real Estate Mortgage Credit Exposure [Member] | Residential Real Estate Mortgage [Member] | Performing [Member]
Credit Quality by Loan Class [Abstract]
Net loans	1,213,077	1,143,300
Originated Loans [Member] | Residential Real Estate Mortgage Credit Exposure [Member] | Residential Real Estate Mortgage [Member] | Nonperforming [Member]
Credit Quality by Loan Class [Abstract]
Net loans	7,337	7,249
Acquired Loans [Member]
Credit Quality by Loan Class [Abstract]
Net loans	340,875	401,691
Acquired Loans [Member] | Commercial Credit Exposure [Member] | Total Commercial, Industrial and Commercial Real Estate [Member]
Credit Quality by Loan Class [Abstract]
Net loans	118,700
Acquired Loans [Member] | Commercial Credit Exposure [Member] | Total Commercial, Industrial and Commercial Real Estate [Member] | Pass [Member]
Credit Quality by Loan Class [Abstract]
Net loans	114,137
Acquired Loans [Member] | Commercial Credit Exposure [Member] | Total Commercial, Industrial and Commercial Real Estate [Member] | Special Mention [Member]
Credit Quality by Loan Class [Abstract]
Net loans	3,918
Acquired Loans [Member] | Commercial Credit Exposure [Member] | Total Commercial, Industrial and Commercial Real Estate [Member] | Substandard [Member]
Credit Quality by Loan Class [Abstract]
Net loans	645
Acquired Loans [Member] | Commercial Credit Exposure [Member] | C&I [Member]
Credit Quality by Loan Class [Abstract]
Net loans	30,871
Acquired Loans [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Pass [Member]
Credit Quality by Loan Class [Abstract]
Net loans	27,046
Acquired Loans [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Special Mention [Member]
Credit Quality by Loan Class [Abstract]
Net loans	3,825
Acquired Loans [Member] | Commercial Credit Exposure [Member] | C&I [Member] | Substandard [Member]
Credit Quality by Loan Class [Abstract]
Net loans	0
Acquired Loans [Member] | Commercial Credit Exposure [Member] | CRE [Member]
Credit Quality by Loan Class [Abstract]
Net loans	87,829
Acquired Loans [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Pass [Member]
Credit Quality by Loan Class [Abstract]
Net loans	87,091
Acquired Loans [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Special Mention [Member]
Credit Quality by Loan Class [Abstract]
Net loans	93
Acquired Loans [Member] | Commercial Credit Exposure [Member] | CRE [Member] | Substandard [Member]
Credit Quality by Loan Class [Abstract]
Net loans	645
Acquired Loans [Member] | Commercial Credit Exposure [Member] | Total Commercial and Agricultural [Member]
Credit Quality by Loan Class [Abstract]
Net loans		146,209
Acquired Loans [Member] | Commercial Credit Exposure [Member] | Total Commercial and Agricultural [Member] | Pass [Member]
Credit Quality by Loan Class [Abstract]
Net loans		141,073
Acquired Loans [Member] | Commercial Credit Exposure [Member] | Total Commercial and Agricultural [Member] | Special Mention [Member]
Credit Quality by Loan Class [Abstract]
Net loans		923
Acquired Loans [Member] | Commercial Credit Exposure [Member] | Total Commercial and Agricultural [Member] | Substandard [Member]
Credit Quality by Loan Class [Abstract]
Net loans		4,213
Acquired Loans [Member] | Commercial Credit Exposure [Member] | Commercial [Member]
Credit Quality by Loan Class [Abstract]
Net loans		39,575
Acquired Loans [Member] | Commercial Credit Exposure [Member] | Commercial [Member] | Pass [Member]
Credit Quality by Loan Class [Abstract]
Net loans		37,825
Acquired Loans [Member] | Commercial Credit Exposure [Member] | Commercial [Member] | Special Mention [Member]
Credit Quality by Loan Class [Abstract]
Net loans		425
Acquired Loans [Member] | Commercial Credit Exposure [Member] | Commercial [Member] | Substandard [Member]
Credit Quality by Loan Class [Abstract]
Net loans		1,325
Acquired Loans [Member] | Commercial Credit Exposure [Member] | Commercial Real Estate [Member]
Credit Quality by Loan Class [Abstract]
Net loans		106,634
Acquired Loans [Member] | Commercial Credit Exposure [Member] | Commercial Real Estate [Member] | Pass [Member]
Credit Quality by Loan Class [Abstract]
Net loans		103,248
Acquired Loans [Member] | Commercial Credit Exposure [Member] | Commercial Real Estate [Member] | Special Mention [Member]
Credit Quality by Loan Class [Abstract]
Net loans		498
Acquired Loans [Member] | Commercial Credit Exposure [Member] | Commercial Real Estate [Member] | Substandard [Member]
Credit Quality by Loan Class [Abstract]
Net loans		2,888
Acquired Loans [Member] | Business Banking Credit Exposure [Member]
Credit Quality by Loan Class [Abstract]
Net loans	35,108	41,104
Acquired Loans [Member] | Business Banking Credit Exposure [Member] | Non-classified [Member]
Credit Quality by Loan Class [Abstract]
Net loans	32,098	38,236
Acquired Loans [Member] | Business Banking Credit Exposure [Member] | Classified [Member]
Credit Quality by Loan Class [Abstract]
Net loans	3,010	2,868
Acquired Loans [Member] | Business Banking Credit Exposure [Member] | Business Banking [Member]
Credit Quality by Loan Class [Abstract]
Net loans	35,108	41,104
Acquired Loans [Member] | Business Banking Credit Exposure [Member] | Business Banking [Member] | Non-classified [Member]
Credit Quality by Loan Class [Abstract]
Net loans	32,098	38,236
Acquired Loans [Member] | Business Banking Credit Exposure [Member] | Business Banking [Member] | Classified [Member]
Credit Quality by Loan Class [Abstract]
Net loans	3,010	2,868
Acquired Loans [Member] | Consumer Credit Exposure [Member]
Credit Quality by Loan Class [Abstract]
Net loans	33,994	43,906
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Performing [Member]
Credit Quality by Loan Class [Abstract]
Net loans	33,719	43,531
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Nonperforming [Member]
Credit Quality by Loan Class [Abstract]
Net loans	275	375
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Dealer Finance [Member]
Credit Quality by Loan Class [Abstract]
Net loans	103
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Dealer Finance [Member] | Performing [Member]
Credit Quality by Loan Class [Abstract]
Net loans	103
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Dealer Finance [Member] | Nonperforming [Member]
Credit Quality by Loan Class [Abstract]
Net loans	0
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Direct [Member]
Credit Quality by Loan Class [Abstract]
Net loans	33,891	2,816
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Direct [Member] | Performing [Member]
Credit Quality by Loan Class [Abstract]
Net loans	33,616
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Direct [Member] | Nonperforming [Member]
Credit Quality by Loan Class [Abstract]
Net loans	275
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Indirect [Member]
Credit Quality by Loan Class [Abstract]
Net loans		1,218
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Indirect [Member] | Performing [Member]
Credit Quality by Loan Class [Abstract]
Net loans		1,195
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Indirect [Member] | Nonperforming [Member]
Credit Quality by Loan Class [Abstract]
Net loans		23
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Home Equity [Member]
Credit Quality by Loan Class [Abstract]
Net loans		39,872
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Home Equity [Member] | Performing [Member]
Credit Quality by Loan Class [Abstract]
Net loans		39,544
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Home Equity [Member] | Nonperforming [Member]
Credit Quality by Loan Class [Abstract]
Net loans		328
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Direct [Member]
Credit Quality by Loan Class [Abstract]
Net loans		2,816
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Direct [Member] | Performing [Member]
Credit Quality by Loan Class [Abstract]
Net loans		2,792
Acquired Loans [Member] | Consumer Credit Exposure [Member] | Direct [Member] | Nonperforming [Member]
Credit Quality by Loan Class [Abstract]
Net loans		24
Acquired Loans [Member] | Residential Real Estate Mortgage Credit Exposure [Member]
Credit Quality by Loan Class [Abstract]
Net loans	153,073	170,472
Acquired Loans [Member] | Residential Real Estate Mortgage Credit Exposure [Member] | Performing [Member]
Credit Quality by Loan Class [Abstract]
Net loans	151,635	168,901
Acquired Loans [Member] | Residential Real Estate Mortgage Credit Exposure [Member] | Nonperforming [Member]
Credit Quality by Loan Class [Abstract]
Net loans	1,438	1,571
Acquired Loans [Member] | Residential Real Estate Mortgage Credit Exposure [Member] | Residential Real Estate Mortgage [Member]
Credit Quality by Loan Class [Abstract]
Net loans	153,073	170,472
Acquired Loans [Member] | Residential Real Estate Mortgage Credit Exposure [Member] | Residential Real Estate Mortgage [Member] | Performing [Member]
Credit Quality by Loan Class [Abstract]
Net loans	151,635	168,901
Acquired Loans [Member] | Residential Real Estate Mortgage Credit Exposure [Member] | Residential Real Estate Mortgage [Member] | Nonperforming [Member]
Credit Quality by Loan Class [Abstract]
Net loans	$ 1,438	$ 1,571

Allowance for Loan Losses an_11

Allowance for Loan Losses and Credit Quality of Loans, Troubled Debt Restructured Loans (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018USD ($)Contract	Sep. 30, 2017USD ($)Contract	Sep. 30, 2018USD ($)Contract	Sep. 30, 2017USD ($)Contract
Troubled Debt Restructured Loans [Abstract]
Number of contracts | Contract	8	6	25	23
Pre-modification outstanding recorded investment	$ 90	$ 714	$ 918	$ 5,235
Post-modification outstanding recorded investment	$ 89	$ 747	$ 918	$ 5,211
Number of contracts | Contract	22	19	54	46
Recorded Investment	$ 1,214	$ 1,181	$ 3,237	$ 2,691
Commercial Loans [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts | Contract			3	2
Pre-modification outstanding recorded investment			$ 369	$ 3,637
Post-modification outstanding recorded investment			$ 371	$ 3,572
Number of contracts | Contract			2	2
Recorded Investment			$ 258	$ 474
Commercial Loans [Member] | Commercial [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts | Contract				1
Pre-modification outstanding recorded investment				$ 3,300
Post-modification outstanding recorded investment				$ 3,239
Number of contracts | Contract			0	1
Recorded Investment			$ 0	$ 145
Commercial Loans [Member] | Business Banking [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts | Contract			3	1
Pre-modification outstanding recorded investment			$ 369	$ 337
Post-modification outstanding recorded investment			$ 371	$ 333
Number of contracts | Contract			2	1
Recorded Investment			$ 258	$ 329
Consumer Loans [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts | Contract	8	5	17	13
Pre-modification outstanding recorded investment	$ 90	$ 196	$ 226	$ 532
Post-modification outstanding recorded investment	$ 89	$ 229	$ 224	$ 571
Number of contracts | Contract	17	13	35	32
Recorded Investment	$ 816	$ 635	$ 1,740	$ 1,400
Consumer Loans [Member] | Indirect [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts | Contract		1		4
Pre-modification outstanding recorded investment		$ 7		$ 39
Post-modification outstanding recorded investment		$ 7		$ 37
Number of contracts | Contract	0	1	0	2
Recorded Investment	$ 0	$ 13	$ 0	$ 19
Consumer Loans [Member] | Dealer Finance [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts | Contract	8		15
Pre-modification outstanding recorded investment	$ 90		$ 185
Post-modification outstanding recorded investment	$ 89		$ 183
Consumer Loans [Member] | Home Equity [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts | Contract		4		8
Pre-modification outstanding recorded investment		$ 189		$ 373
Post-modification outstanding recorded investment		$ 222		$ 414
Number of contracts | Contract	0	12	0	30
Recorded Investment	$ 0	$ 622	$ 0	$ 1,381
Consumer Loans [Member] | Direct [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts | Contract			2	1
Pre-modification outstanding recorded investment			$ 41	$ 120
Post-modification outstanding recorded investment			$ 41	$ 120
Number of contracts | Contract	17	0	35	0
Recorded Investment	$ 816	$ 0	$ 1,740	$ 0
Residential Real Estate [Member]
Troubled Debt Restructured Loans [Abstract]
Number of contracts | Contract		1	5	8
Pre-modification outstanding recorded investment		$ 518	$ 323	$ 1,066
Post-modification outstanding recorded investment		$ 518	$ 323	$ 1,068
Number of contracts | Contract	5	6	17	12
Recorded Investment	$ 398	$ 546	$ 1,239	$ 817

Defined Benefit Post-Retireme_4

Defined Benefit Post-Retirement Plans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Defined Benefit Post-Retirement Plans [Abstract]
Employer contributions	$ 0	$ 0	$ 0	$ 0
Pension Benefits [Member]
Components of net periodic (benefit) cost [Abstract]
Service cost	415	329	1,256	1,133
Interest cost	912	1,043	2,752	3,127
Expected return on plan assets	(2,119)	(1,976)	(6,364)	(5,946)
Net amortization	242	454	745	1,284
Total net periodic (benefit) cost	(550)	(150)	(1,611)	(402)
Other Benefits [Member]
Components of net periodic (benefit) cost [Abstract]
Service cost	3	3	8	9
Interest cost	82	88	245	259
Expected return on plan assets	0	0	0	0
Net amortization	44	26	131	66
Total net periodic (benefit) cost	$ 129	$ 117	$ 384	$ 334

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Basic EPS [Abstract]
Weighted average common shares outstanding (in shares)	43,714,000	43,595,000	43,692,000	43,563,000
Net income available to common stockholders	$ 29,807	$ 22,876	$ 83,914	$ 64,514
Basic EPS (in dollars per share)	$ 0.68	$ 0.52	$ 1.92	$ 1.48
Diluted EPS [Abstract]
Weighted average common shares outstanding (in shares)	43,714,000	43,595,000	43,692,000	43,563,000
Dilutive effect of common stock options and restricted stock (in shares)	337,000	320,000	317,000	329,000
Weighted average common shares and common share equivalents (in shares)	44,051,000	43,915,000	44,009,000	43,892,000
Net income available to common stockholders	$ 29,807	$ 22,876	$ 83,914	$ 64,514
Diluted EPS (in dollars per share)	$ 0.68	$ 0.52	$ 1.91	$ 1.47
Stock Options [Member]
Earnings Per Share [Abstract]
Stock options excluded from calculation of diluted EPS (in shares)	1,500	3,250	1,500	3,014

Reclassification Adjustments _3

Reclassification Adjustments Out of Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income (Loss) [Abstract]
Net securities losses	$ 412	$ (4)	$ 575	$ (2)
Interest income	77,527	71,930	226,754	210,042
Other noninterest income	3,048	3,945	11,341	10,069
Other noninterest expense	4,577	4,483	13,324	13,880
Interest expense	10,677	6,917	26,977	19,135
Income tax (expense) benefit	8,578	11,342	23,699	30,321
Net income	29,807	22,876	83,914	64,514
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income (Loss) [Abstract]
Total reclassifications during the period, net of tax	(138)	334	(96)	2,004
Accumulated Net Unrealized Investment Gain (Loss) [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income (Loss) [Abstract]
Income tax (expense) benefit	(42)	(83)	(133)	(760)
Net income	126	133	400	1,229
Losses on AFS Securities [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income (Loss) [Abstract]
Net securities losses	0	4	0	2
Amortization of Unrealized Gains Related to Securities Transfer [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income (Loss) [Abstract]
Interest income	168	212	533	675
Impairment Write-Down of Equity Security [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income (Loss) [Abstract]
Other noninterest income			0	1,312
Net Unrealized (Gains) on Cash Flow hedges Reclassified to Interest (Income) [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income (Loss) [Abstract]
Interest expense	(638)	(155)	(1,537)	(96)
Income tax (expense) benefit	159	59	384	37
Net income	(479)	(96)	(1,153)	(59)
Accumulated Defined Benefit Plans Adjustment [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income (Loss) [Abstract]
Income tax (expense) benefit	(71)	(183)	(219)	(516)
Net income	215	297	657	834
Amortization of Net Losses [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income (Loss) [Abstract]
Other noninterest expense	263	481	809	1,351
Amortization of Prior Service Costs [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income (Loss) [Abstract]
Other noninterest expense	$ 23	$ (1)	$ 67	$ (1)

Fair Value Measurements and F_4

Fair Value Measurements and Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Transfers between Levels [Abstract]
Transfers from Level 1 to Level 2	$ 0	$ 0
Transfers from Level 2 to Level 1	4,000	0
Transfers into Level 3		0
Transfers out of Level 3		0
AFS securities [Abstract]
AFS securities	1,101,074
Total AFS securities	1,101,074	1,255,925
Equity securities	24,722	0
Trading securities	0	11,467
Liabilities [Abstract]
Collateral dependent loans	25	100
Collateral dependent loans, specific reserves	$ 25	100
Minimum [Member]
Liabilities [Abstract]
Liquidation expense ratio on impaired collateral	10.00%
Maximum [Member]
Liabilities [Abstract]
Liquidation expense ratio on impaired collateral	35.00%
Federal Agency [Member]
AFS securities [Abstract]
AFS securities	$ 83,262	108,899
State & Municipal [Member]
AFS securities [Abstract]
AFS securities	36,467	41,956
Recurring Basis [Member]
AFS securities [Abstract]
AFS securities	1,101,074
Other securities		14,149
Total AFS securities		1,255,925
Equity securities	24,722
Trading securities		11,467
Derivatives	23,682	3,732
Total	1,149,478	1,271,124
Liabilities [Abstract]
Derivatives	20,054	324
Total	20,054	324
Recurring Basis [Member] | Level 1 [Member]
AFS securities [Abstract]
AFS securities	0
Other securities		5,845
Total AFS securities		5,845
Equity securities	20,722
Trading securities		11,467
Derivatives	0	0
Total	20,722	17,312
Liabilities [Abstract]
Derivatives	0	0
Total	0	0
Recurring Basis [Member] | Level 2 [Member]
AFS securities [Abstract]
AFS securities	1,101,074
Other securities		8,304
Total AFS securities		1,250,080
Equity securities	4,000
Trading securities		0
Derivatives	23,682	3,732
Total	1,128,756	1,253,812
Liabilities [Abstract]
Derivatives	20,054	324
Total	20,054	324
Recurring Basis [Member] | Level 3 [Member]
AFS securities [Abstract]
AFS securities	0
Other securities		0
Total AFS securities		0
Equity securities	0
Trading securities		0
Derivatives	0	0
Total	0	0
Liabilities [Abstract]
Derivatives	0	0
Total	0	0
Recurring Basis [Member] | Federal Agency [Member]
AFS securities [Abstract]
AFS securities	83,262	108,899
Recurring Basis [Member] | Federal Agency [Member] | Level 1 [Member]
AFS securities [Abstract]
AFS securities	0	0
Recurring Basis [Member] | Federal Agency [Member] | Level 2 [Member]
AFS securities [Abstract]
AFS securities	83,262	108,899
Recurring Basis [Member] | Federal Agency [Member] | Level 3 [Member]
AFS securities [Abstract]
AFS securities	0	0
Recurring Basis [Member] | State & Municipal [Member]
AFS securities [Abstract]
AFS securities	36,467	41,956
Recurring Basis [Member] | State & Municipal [Member] | Level 1 [Member]
AFS securities [Abstract]
AFS securities	0	0
Recurring Basis [Member] | State & Municipal [Member] | Level 2 [Member]
AFS securities [Abstract]
AFS securities	36,467	41,956
Recurring Basis [Member] | State & Municipal [Member] | Level 3 [Member]
AFS securities [Abstract]
AFS securities	0	0
Recurring Basis [Member] | Mortgage-Backed [Member]
AFS securities [Abstract]
AFS securities	492,408	554,927
Recurring Basis [Member] | Mortgage-Backed [Member] | Level 1 [Member]
AFS securities [Abstract]
AFS securities	0	0
Recurring Basis [Member] | Mortgage-Backed [Member] | Level 2 [Member]
AFS securities [Abstract]
AFS securities	492,408	554,927
Recurring Basis [Member] | Mortgage-Backed [Member] | Level 3 [Member]
AFS securities [Abstract]
AFS securities	0	0
Recurring Basis [Member] | Collateralized Mortgage Obligations [Member]
AFS securities [Abstract]
AFS securities	488,937	535,994
Recurring Basis [Member] | Collateralized Mortgage Obligations [Member] | Level 1 [Member]
AFS securities [Abstract]
AFS securities	0	0
Recurring Basis [Member] | Collateralized Mortgage Obligations [Member] | Level 2 [Member]
AFS securities [Abstract]
AFS securities	488,937	535,994
Recurring Basis [Member] | Collateralized Mortgage Obligations [Member] | Level 3 [Member]
AFS securities [Abstract]
AFS securities	$ 0	$ 0

Fair Value Measurements and F_5

Fair Value Measurements and Fair Value of Financial Instruments, Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Interest Rate Swaps [Abstract]
Reclassification of net unrealized gains (losses) on cash flow hedges from AOCI to interest expense	$ 479	$ 96	$ 1,153	$ 59
Financial assets [Abstract]
HTM securities	645,732		645,732		$ 481,871
Financial liabilities [Abstract]
Time deposits	868,569		868,569		806,766
Long-term debt	73,751		73,751		88,869
Junior subordinated debt	101,196		101,196		101,196
Carrying Amount [Member] | Level 2 [Member]
Financial assets [Abstract]
HTM securities	659,949		659,949		484,073
Financial liabilities [Abstract]
Time deposits	868,569		868,569		806,766
Long-term debt	73,751		73,751		88,869
Junior subordinated debt	101,196		101,196		101,196
Carrying Amount [Member] | Level 3 [Member]
Financial assets [Abstract]
Net loans	6,819,492		6,819,492		6,515,273
Estimated Fair Value [Member] | Level 2 [Member]
Financial assets [Abstract]
HTM securities	645,732		645,732		481,871
Financial liabilities [Abstract]
Time deposits	860,791		860,791		801,294
Long-term debt	72,152		72,152		88,346
Junior subordinated debt	102,979		102,979		104,593
Estimated Fair Value [Member] | Level 3 [Member]
Financial assets [Abstract]
Net loans	6,762,901		6,762,901		6,651,931
Not Designated as Hedging Instrument [Member] | Interest Rate Swaps [Member] | Other Assets [Member]
Interest Rate Swaps [Abstract]
Derivative asset, notional amount	630,200		630,200		481,200
Fair value of derivative asset	20,000		20,000		200
Not Designated as Hedging Instrument [Member] | Interest Rate Swaps [Member] | Other Liabilities [Member]
Interest Rate Swaps [Abstract]
Derivative liability, notional amount	630,200		630,200		481,200
Fair value of derivative liability	20,000		20,000		200
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | Interest Rate Swaps [Member]
Interest Rate Swaps [Abstract]
Notional amount	225,000		225,000		250,000
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | Interest Rate Swaps [Member] | Interest Expense [Member]
Interest Rate Swaps [Abstract]
Reclassification of net unrealized gains (losses) on cash flow hedges from AOCI to interest expense	600	$ 200	1,500	$ 100
Amount expected to be reclassified as a reduction to interest expense for CF hedges	3,000		3,000
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | Interest Rate Swaps [Member] | Other Assets [Member]
Interest Rate Swaps [Abstract]
Fair value of derivative asset	$ 3,600		$ 3,600		$ 3,500

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Commitment to Extend Credits and Unused Lines of Credit [Member]
Guarantor Obligations [Abstract]
Commitments - maximum potential obligation	$ 1,700	$ 1,600
Standby Letters of Credit [Member]
Guarantor Obligations [Abstract]
Obligation instrument term	5 years
Commitments - maximum potential obligation	$ 39.5	$ 41.1

Revenue from Contracts with C_4

Revenue from Contracts with Customers (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Noninterest Income [Abstract]
Total noninterest income in-scope of ASC 606	$ 31,681	$ 29,498	$ 94,389	$ 85,921
Total noninterest income out-of-scope of ASC 606	1,700	1,280	4,427	3,911
Total noninterest income	33,381	30,778	98,816	89,832
Insurance and Other Financial Services Revenue [Member]
Noninterest Income [Abstract]
Total noninterest income in-scope of ASC 606	6,172	5,536	18,502	17,927
Service Charges on Deposit Accounts [Member]
Noninterest Income [Abstract]
Total noninterest income in-scope of ASC 606	4,503	4,261	12,721	12,399
ATM and Debit Card Fees [Member]
Noninterest Income [Abstract]
Total noninterest income in-scope of ASC 606	5,906	5,557	16,995	16,025
Retirement Plan Administration Fees [Member]
Noninterest Income [Abstract]
Total noninterest income in-scope of ASC 606	7,244	5,272	19,879	14,881
Trust [Member]
Noninterest Income [Abstract]
Total noninterest income in-scope of ASC 606	4,808	4,927	14,951	14,620
Other [Member]
Noninterest Income [Abstract]
Total noninterest income in-scope of ASC 606	$ 3,048	$ 3,945	$ 11,341	$ 10,069

Recent Accounting Pronounceme_3

Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Recent Accounting Pronouncements [Abstract]
Federal corporate tax rate	21.00%	35.00%
ASU 2018-02 [Member]
Recent Accounting Pronouncements [Abstract]
Reclassification upon ASU implementation		$ 0
AOCI [Member] | ASU 2016-01 [Member]
Recent Accounting Pronouncements [Abstract]
Reclassification upon ASU implementation		(2,600)
Retained Earnings [Member] | ASU 2016-01 [Member]
Recent Accounting Pronouncements [Abstract]
Reclassification upon ASU implementation		2,600
AOCI [Member] | ASU 2018-02 [Member]
Recent Accounting Pronouncements [Abstract]
Reclassification upon ASU implementation		(5,575)
Retained Earnings [Member] | ASU 2018-02 [Member]
Recent Accounting Pronouncements [Abstract]
Reclassification upon ASU implementation		$ 5,575

Subsequent Events (Details)

Subsequent Events (Details) $ in Millions	3 Months Ended
	Dec. 31, 2018USD ($)
Subsequent Event [Member]
Subsequent Event [Line Items]
Tax benefit resulting from letter ruling from the IRS	$ 4.7