Community Bank System (CBU) 10-Q 12 Nov 19 2019 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2019	Oct. 31, 2019
Cover [Abstract]
Entity Registrant Name	COMMUNITY BANK SYSTEM, INC.
Entity Central Index Key	0000723188
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		51,701,790
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Document Quarterly Report	true
Document Transition Report	false
Entity File Number	001-13695
Entity Tax Identification Number	16-1213679
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	5790 Widewaters Parkway
Entity Address, City or Town	DeWitt
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	13214
City Area Code	315
Local Phone Number	445-2282
Title of 12(b) Security	Common Stock, $1.00 par value per share
Trading Symbol	CBU
Security Exchange Name	NYSE

CONSOLIDATED STATEMENTS OF COND

CONSOLIDATED STATEMENTS OF CONDITION (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Assets:
Cash and cash equivalents	$ 1,014,042	$ 211,834
Available-for-sale investment securities (cost of $2,392,004 and $2,952,278, respectively)	2,437,102	2,936,049
Equity and other securities (cost of $43,680 and $44,678, respectively)	44,640	45,609
Loans held for sale, at fair value	0	83
Loans	6,853,191	6,281,121
Allowance for loan losses	(49,423)	(49,284)
Net loans	6,803,768	6,231,837
Goodwill, net	773,610	733,503
Core deposit intangibles, net	17,872	18,596
Other intangibles, net	49,203	55,250
Intangible assets, net	840,685	807,349
Premises and equipment, net	169,933	119,988
Accrued interest and fees receivable	34,126	31,048
Other assets	253,001	223,498
Total assets	11,597,297	10,607,295
Liabilities:
Noninterest-bearing deposits	2,549,395	2,312,816
Interest-bearing deposits	6,618,890	6,009,555
Total deposits	9,168,285	8,322,371
Short-term borrowings	0	54,400
Securities sold under agreement to repurchase, short-term	233,333	259,367
Other long-term debt	4,328	1,976
Subordinated notes payable	13,814	0
Subordinated debt held by unconsolidated subsidiary trusts	77,320	97,939
Accrued interest and other liabilities	259,796	157,459
Total liabilities	9,756,876	8,893,512
Commitments and contingencies (See Note K)
Shareholders' equity:
Preferred stock, $1.00 par value, 500,000 shares authorized, 0 shares issued	0	0
Common stock, $1.00 par value, 75,000,000 shares authorized; 51,842,966 and 51,576,839 shares issued, respectively	51,843	51,577
Additional paid-in capital	921,682	911,748
Retained earnings	861,254	795,563
Accumulated other comprehensive income (loss)	2,470	(45,305)
Treasury stock, at cost (182,912 shares, including 178,361 shares held by deferred compensation arrangements at September 30, 2019 and 319,015 shares including 207,403 shares held by deferred compensation arrangements at December 31, 2018, respectively)	(6,875)	(11,528)
Deferred compensation arrangements (178,361 and 207,403 shares, respectively)	10,047	11,728
Total shareholders' equity	1,840,421	1,713,783
Total liabilities and shareholders' equity	$ 11,597,297	$ 10,607,295

CONSOLIDATED STATEMENTS OF CO_2

CONSOLIDATED STATEMENTS OF CONDITION (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Assets:
Available-for-sale investment securities, cost	$ 2,392,004	$ 2,952,278
Equity and other securities, cost	$ 43,680	$ 44,678
Shareholders' equity:
Preferred stock, par value (in dollars per share)	$ 1	$ 1
Preferred stock, shares authorized (in shares)	500,000	500,000
Preferred stock, shares issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	75,000,000	75,000,000
Common stock, shares issued (in shares)	51,842,966	51,576,839
Treasury stock, shares at cost (in shares)	182,912	319,015
Shares held by deferred compensation arrangements (in shares)	178,361	207,403

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Interest income:
Interest and fees on loans	$ 79,931	$ 72,256	$ 227,701	$ 212,849
Interest and dividends on taxable investments	15,862	15,421	49,376	47,462
Interest on nontaxable investments	2,854	3,226	8,603	10,001
Total interest income	98,647	90,903	285,680	270,312
Interest expense:
Interest on deposits	5,859	2,764	14,526	7,277
Interest on borrowings	347	796	1,397	1,722
Interest on subordinated notes payable	161	0	161	0
Interest on subordinated debt held by unconsolidated subsidiary trusts	1,004	1,145	3,161	3,645
Total interest expense	7,371	4,705	19,245	12,644
Net interest income	91,276	86,198	266,435	257,668
Provision for loan losses	1,751	2,215	5,573	8,342
Net interest income after provision for loan losses	89,525	83,983	260,862	249,326
Noninterest revenues:
Deposit service fees	16,920	16,127	48,780	54,268
Other banking revenues	945	1,536	3,628	3,942
Employee benefit services	24,329	23,265	72,170	68,813
Insurance services	8,527	8,270	24,718	23,044
Wealth management services	6,363	6,168	19,290	19,370
Gain on sales of investment securities, net	0	0	4,882	0
Unrealized gain on equity securities	10	743	28	722
Loss on debt extinguishment	0	(318)	0	(318)
Total noninterest revenues	57,094	55,791	173,496	169,841
Noninterest expenses:
Salaries and employee benefits	56,061	51,062	163,448	155,323
Occupancy and equipment	9,801	9,770	29,708	29,738
Data processing and communications	10,675	10,509	30,475	29,463
Amortization of intangible assets	3,960	4,427	11,994	13,780
Legal and professional fees	2,595	2,522	7,999	8,047
Business development and marketing	2,604	2,587	8,532	7,301
Acquisition expenses	6,061	(832)	7,789	(769)
Other expenses	5,172	5,188	16,812	14,793
Total noninterest expenses	96,929	85,233	276,757	257,676
Income before income taxes	49,690	54,541	157,601	161,491
Income taxes	10,472	11,435	31,422	33,673
Net income	$ 39,218	$ 43,106	$ 126,179	$ 127,818
Basic earnings per share (in dollars per share)	$ 0.76	$ 0.84	$ 2.44	$ 2.49
Diluted earnings per share (in dollars per share)	$ 0.75	$ 0.83	$ 2.41	$ 2.46

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Pension and other post retirement obligations:
Amortization of actuarial losses included in net periodic pension cost, gross	$ 651	$ 304	$ 1,954	$ 910
Tax effect	(158)	(74)	(477)	(221)
Amortization of actuarial losses included in net periodic pension cost, net	493	230	1,477	689
Amortization of prior service cost included in net periodic pension cost, gross	(28)	(105)	(86)	(359)
Tax effect	6	25	21	87
Amortization of prior service cost included in net periodic pension cost, net	(22)	(80)	(65)	(272)
Initial projected benefit obligation recognized upon plan adoption, gross	0	(775)	0	(775)
Tax effect	0	189	0	189
Initial projected benefit obligation recognized upon plan adoption, net	0	(586)	0	(586)
Other comprehensive income (loss) related to pension and other post-retirement obligations, net of taxes	471	(436)	1,412	(169)
Unrealized gains (losses) on available-for-sale securities:
Net unrealized holding gains (losses) arising during period, gross	8,756	(20,094)	66,208	(76,705)
Tax effect	(2,136)	4,879	(16,157)	18,639
Net unrealized holding gains (losses) arising during period, net	6,620	(15,215)	50,051	(58,066)
Reclassification adjustment for net gains included in net income, gross	0	0	(4,882)	0
Tax effect	0	0	1,194	0
Reclassification adjustment for net gains included in net income, net	0	0	(3,688)	0
Reclassification of other comprehensive income due to change in accounting principle - equity securities	0	0	0	(208)
Other comprehensive income/(loss) related to unrealized gains (losses) on available-for-sale securities, net of taxes	6,620	(15,215)	46,363	(58,274)
Other comprehensive income (loss), net of tax	7,091	(15,651)	47,775	(58,443)
Net income	39,218	43,106	126,179	127,818
Comprehensive income	46,309	$ 27,455	173,954	$ 69,375
Accumulated Other Comprehensive Income (Loss) By Component:
Unrealized (loss) for pension and other post-retirement obligations	(41,629)		(41,629)		$ (43,497)
Tax effect	10,204		10,204		10,660
Net unrealized (loss) for pension and other post-retirement obligations	(31,425)		(31,425)		(32,837)
Unrealized gain (loss) on available-for-sale securities	45,097		45,097		(16,229)
Tax effect	(10,994)		(10,994)		3,969
Reclassification of other comprehensive income due to change in accounting principle - equity securities	(208)		(208)		(208)
Net unrealized gain (loss) on available-for-sale securities	33,895		33,895		(12,468)
Accumulated other comprehensive income (loss)	$ 2,470		$ 2,470		$ (45,305)

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Common Stock Shares Outstanding [Member]	Common Stock Amount Issued [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive (Loss) [Member]	Treasury Stock [Member]	Deferred Compensation Arrangements [Member]	Total
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of change in accounting principle - equity securities				$ 208	$ (208)			$ 0
Balance at Dec. 31, 2017		$ 51,264	$ 894,879	700,557	(3,699)	$ (21,014)	$ 13,328	1,635,315
Balance (in shares) at Dec. 31, 2017	50,696,077
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income				127,818				127,818
Other comprehensive income (loss), net of tax					(58,235)			(58,235)
Cash dividends declared:
Common				(54,180)				(54,180)
Common stock activity under employee stock ownership plan		283	5,511					5,794
Common stock activity under employee stock ownership plan (in shares)	283,412
Stock-based compensation			4,607					4,607
Distribution of stock under deferred compensation arrangements						1,898	(1,898)	0
Distribution of stock under deferred compensation arrangements (in shares)	35,233
Treasury stock issued to benefit plans, net			2,693			4,313	220	7,226
Treasury stock issued to benefit plans, net (in shares)	121,954
Balance at Sep. 30, 2018		51,547	907,690	774,403	(62,142)	(14,803)	11,650	1,668,345
Balance (in shares) at Sep. 30, 2018	51,136,676
Balance at Jun. 30, 2018		51,512	904,913	750,779	(46,491)	(15,334)	11,580	1,656,959
Balance (in shares) at Jun. 30, 2018	51,085,874
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income				43,106				43,106
Other comprehensive income (loss), net of tax					(15,651)			(15,651)
Cash dividends declared:
Common				(19,482)				(19,482)
Common stock activity under employee stock ownership plan		35	1,115					1,150
Common stock activity under employee stock ownership plan (in shares)	35,261
Stock-based compensation			1,211					1,211
Treasury stock issued to benefit plans, net			451			531	70	1,052
Treasury stock issued to benefit plans, net (in shares)	15,541
Balance at Sep. 30, 2018		51,547	907,690	774,403	(62,142)	(14,803)	11,650	1,668,345
Balance (in shares) at Sep. 30, 2018	51,136,676
Balance at Dec. 31, 2018		51,577	911,748	795,563	(45,305)	(11,528)	11,728	1,713,783
Balance (in shares) at Dec. 31, 2018	51,257,824
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income				126,179				126,179
Other comprehensive income (loss), net of tax					47,775			47,775
Cash dividends declared:
Common				(60,488)				(60,488)
Common stock activity under employee stock ownership plan		266	2,246					2,512
Common stock activity under employee stock ownership plan (in shares)	266,127
Stock-based compensation			3,998					3,998
Distribution of stock under deferred compensation arrangements			1,064			830	(1,894)	0
Distribution of stock under deferred compensation arrangements (in shares)	32,431
Treasury stock issued to benefit plans, net			2,626			3,823	213	6,662
Treasury stock issued to benefit plans, net (in shares)	103,672
Balance at Sep. 30, 2019		51,843	921,682	861,254	2,470	(6,875)	10,047	1,840,421
Balance (in shares) at Sep. 30, 2019	51,660,054
Balance at Jun. 30, 2019		51,806	917,855	843,288	(4,621)	(8,797)	9,979	1,809,510
Balance (in shares) at Jun. 30, 2019	51,570,608
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income				39,218				39,218
Other comprehensive income (loss), net of tax					7,091			7,091
Cash dividends declared:
Common				(21,252)				(21,252)
Common stock activity under employee stock ownership plan		37	1,254					1,291
Common stock activity under employee stock ownership plan (in shares)	37,542
Stock-based compensation			1,241					1,241
Treasury stock issued to benefit plans, net			1,332			1,922	68	3,322
Treasury stock issued to benefit plans, net (in shares)	51,904
Balance at Sep. 30, 2019		$ 51,843	$ 921,682	$ 861,254	$ 2,470	$ (6,875)	$ 10,047	$ 1,840,421
Balance (in shares) at Sep. 30, 2019	51,660,054

CONSOLIDATED STATEMENTS OF CH_2

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Unaudited) (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Cash dividends declared:
Dividends declared per common share (in dollars per share)	$ 0.41	$ 0.38	$ 1.17	$ 1.06

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Operating activities:
Net income	$ 126,179	$ 127,818
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	11,781	11,854
Amortization of intangible assets	11,994	13,780
Net accretion on securities, loans and borrowings	(4,545)	(7,141)
Stock-based compensation	3,998	4,607
Provision for loan losses	5,573	8,342
Amortization of mortgage servicing rights	285	340
Gain on sale of investment securities, net	(4,882)	0
Unrealized gain on equity securities	(28)	(722)
Loss on debt extinguishment	0	318
Income from bank-owned life insurance policies	(1,215)	(1,177)
Net gain on sale of loans and other assets	(2)	(207)
Change in other assets and other liabilities	(20,152)	9,966
Net cash provided by operating activities	128,986	167,778
Investing activities:
Proceeds from sales of available-for-sale investment securities	590,179	0
Proceeds from maturities, calls, and paydowns of available-for-sale investment securities	153,785	102,549
Proceeds from maturities and redemptions of equity and other investment securities	3,258	8,292
Purchases of available-for-sale investment securities	(86,073)	(47,495)
Purchases of equity and other securities	(144)	(31)
Net increase in loans	(100,020)	(51,170)
Cash paid for acquisitions, net of cash acquired of $90,381 and $16, respectively	(4,653)	(1,737)
Settlement of bank-owned life insurance policies	1,597	0
Purchases of premises and equipment, net	(5,025)	(8,903)
Real estate limited partnership investments	(1,342)	(1,197)
Net cash provided by investing activities	551,562	308
Financing activities:
Net increase in deposits	277,833	19,401
Net decrease in borrowings	(80,502)	(86,523)
Payments on subordinated debt held by unconsolidated subsidiary trusts	(22,681)	(25,207)
Issuance of common stock	2,512	5,794
Purchases of treasury stock	(213)	(220)
Sales of treasury stock	6,662	7,226
Increase in deferred compensation arrangements	213	220
Cash dividends paid	(59,014)	(52,006)
Withholding taxes paid on share-based compensation	(3,150)	(971)
Net cash provided by/(used in) financing activities	121,660	(132,286)
Change in cash and cash equivalents	802,208	35,800
Cash and cash equivalents at beginning of period	211,834	221,038
Cash and cash equivalents at end of period	1,014,042	256,838
Supplemental disclosures of cash flow information:
Cash paid for interest	18,455	12,870
Cash paid for income taxes	34,150	20,674
Supplemental disclosures of noncash financing and investing activities:
Dividends declared and unpaid	21,282	19,634
Transfers from loans to other real estate	1,833	2,426
Acquisitions:
Fair value of assets acquired, excluding acquired cash and intangibles	548,934	115
Fair value of liabilities assumed	$ 589,611	$ 31

CONSOLIDATED STATEMENTS OF CA_2

CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (Parenthetical) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Investing activities:
Cash acquired from acquisition	$ 90,381	$ 16

BASIS OF PRESENTATION

BASIS OF PRESENTATION	9 Months Ended
	Sep. 30, 2019
BASIS OF PRESENTATION [Abstract]
BASIS OF PRESENTATION	NOTE A: BASIS OF PRESENTATION The interim financial data as of and for the three and nine months ended September 30, 2019 is unaudited; however, in the opinion of Community Bank System, Inc. (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 conformity with generally accepted accounting principles in the United States of America (“GAAP”). 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.

ACQUISITIONS

ACQUISITIONS	9 Months Ended
	Sep. 30, 2019
ACQUISITIONS [Abstract]
ACQUISITIONS	NOTE B: ACQUISITIONS Subsequent Event/Pending Acquisition – Steuben Trust Corporation On October 21, 2019, the Company announced that it had entered into a definitive agreement to acquire Steuben Trust Corporation (“Steuben”), parent company of Steuben Trust Company, a New York State chartered bank headquartered in Hornell, New York, for approximately $106.8 million in Company stock and cash. The acquisition will add 15 branch locations, extend the Company’s footprint into two new counties in Western New York State, and enhance the Company’s presence in four Western New York State counties in which it currently operates. The acquisition is expected to close during the second quarter of 2020, pending both customary regulatory and Steuben shareholder approval. The Company expects to incur certain one-time, transaction-related costs in 2019 and 2020 in connection with the Steuben acquisition. On September 18, 2019, the Company, through its subsidiary, Community Investment Services, Inc. (“CISI”), completed its acquisition of certain assets of a practice engaged in the financial services business headquartered in Syracuse, New York. The Company paid $0.5 million in cash to acquire a customer list, and recorded a $0.5 million customer list intangible asset in conjunction with the acquisition. The effects of the acquired assets have been included in the consolidated financial statements since that date. On July 12, 2019, the Company completed its merger with Kinderhook Bank Corp. (“Kinderhook”), parent company of The National Union Bank of Kinderhook, headquartered in Kinderhook, New York, for $93.4 million in cash. The merger added 11 branch locations across a five county area in the Capital District of Upstate New York. The merger resulted in the acquisition of $642.9 million of assets, including $479.9 million of loans and $39.8 million of investment securities, as well as $568.1 million of deposits and $40.1 million in goodwill. The effects of the acquired assets and liabilities have been included in the consolidated financial statements since that date. Revenues, excluding interest income on acquired investments, On January 2, 2019, the Company, through its subsidiary, CISI, completed its acquisition of certain assets of Wealth Resources Network, Inc. (“Wealth Resources”), a financial services business headquartered in Liverpool, New York. The Company paid $1.2 million in cash to acquire a customer list from Wealth Resources, and recorded a $1.2 million customer list intangible asset in conjunction with the acquisition. The effects of the acquired assets have been included in the consolidated financial statements since that date. On April 2, 2018, the Company, through its subsidiary, Benefit Plans Administrative Services, Inc. (“BPAS”), acquired certain assets of HR Consultants (SA), LLC (“HR Consultants”), a provider of actuarial and benefit consulting services headquartered in Puerto Rico. The Company paid $0.3 million in cash to acquire the assets of HR Consultants and recorded intangible assets of $0.3 million in conjunction with the acquisition. The effects of the acquired assets have been included in the consolidated financial statements since that date. On January 2, 2018, the Company, through its subsidiary, OneGroup NY, Inc. (“OneGroup”), completed its acquisition of certain assets of Penna & Associates Agency, Inc. (“Penna”), an insurance agency headquartered in Johnson City, New York. The Company paid $0.8 million in cash to acquire the assets of Penna, and recorded goodwill in the amount of $0.3 million and a customer list intangible asset of $0.3 million in conjunction with the acquisition. The effects of the acquired assets and liabilities have been included in the consolidated financial statements since that date. On January 2, 2018, the Company, through its subsidiary, CISI, completed its acquisition of certain assets of Styles Bridges Associates (“Styles Bridges”), a financial services business headquartered in Canton, New York. The Company paid $0.7 million in cash to acquire a customer list from Styles Bridges, and recorded a $0.7 million customer list intangible asset in conjunction with the acquisition. The effects of the acquired assets have been included in the consolidated financial statements since that date. The assets and liabilities assumed in the acquisitions were recorded at their estimated fair values based on management's best estimates using information available at the dates of the acquisitions, and were subject to adjustment based on updated information not available at the time of the acquisitions. The accrued income taxes associated with the Kinderhook acquisition were recorded on a provisional basis and could vary from the actual recorded balance once finalized. The above referenced acquisitions generally expanded the Company’s geographical presence in New York and management expects that the Company will benefit from greater geographic diversity and the advantages of other synergistic business development opportunities. The following table summarizes the estimated fair value of the assets acquired and liabilities assumed after considering the measurement period adjustments described above: 2019 2018 (000s omitted) Kinderhook Other (1) Total Other (2) Consideration paid : Cash $ 93,384 $ 1,650 $ 95,034 $ 1,753 Total net consideration paid $ 93,384 $ 1,650 $ 95,034 $ 1,753 Recognized amounts of identifiable assets acquired and liabilities assumed: Cash and cash equivalents 90,381 0 90,381 16 Available-for-sale investment securities 37,653 0 37,653 0 Equity and other securities 2,117 0 2,117 0 Loans 479,931 0 479,931 0 Premises and equipment 13,970 0 13,970 10 Accrued interest and fees receivable 1,119 0 1,119 0 Other assets 14,144 0 14,144 105 Core deposit intangibles 3,573 0 3,573 0 Other intangibles 0 1,650 1,650 1,343 Deposits (568,081 ) 0 (568,081 ) 0 Other liabilities (3,217 ) 0 (3,217 ) (31 ) Subordinated notes payable (13,831 ) 0 (13,831 ) 0 Other long-term debt (2,420 ) 0 (2,420 ) 0 Subordinated debt held by unconsolidated subsidiary trusts (2,062 ) 0 (2,062 ) 0 Total identifiable assets, net 53,277 1,650 54,927 1,443 Goodwill $ 40,107 $ 0 $ 40,107 $ 310 (1) completed by CISI in 2019. (2) Acquired loans that have evidence of deterioration in credit quality since origination and for which it is probable, at acquisition, that the Company will be unable to collect all contractually required payments were aggregated by comparable characteristics and recorded at fair value without a carryover of the related allowance for loan losses. Cash flows for each loan were determined using an estimate of credit losses and rate of prepayments. Projected monthly cash flows were then discounted to present value using a market-based discount rate. The excess of the undiscounted expected cash flows over the estimated fair value is referred to as the “accretable yield” and is recognized into interest income over the remaining lives of the acquired loans. The following is a summary of the loans acquired from Kinderhook at the date of acquisition: (000s omitted) Acquired Impaired Loans Acquired Non-impaired Loans Total Acquired Loans Contractually required principal and interest at acquisition $ 12,661 $ 591,694 $ 604,355 Contractual cash flows not expected to be collected (4,096 ) (5,472 ) (9,568 ) Expected cash flows at acquisition 8,565 586,222 594,787 Interest component of expected cash flows (512 ) (114,344 ) (114,856 ) Fair value of acquired loans $ 8,053 $ 471,878 $ 479,931 The fair value of checking, savings and money market deposit accounts acquired were assumed to approximate the carrying value as these accounts have no stated maturity and are payable on demand. Certificate of deposit accounts were valued at the present value of the certificates’ expected contractual payments discounted at market rates for similar certificates. The fair value of subordinated notes payable was estimated using discounted cash flows and interest rates being offered on similar securities. Subordinated notes payable assumed with the Kinderhook acquisition included $3.0 million of subordinated notes with a fixed interest rate of 6.0% maturing in February 2028 November 2025 The core deposit intangibles and other intangibles related to both acquisitions completed by CISI in 2019 Direct costs related to the acquisitions were expensed as incurred. Merger and acquisition integration-related expenses amount to $6.1 million and $7.8 million during the three and nine months ended September 30, 2019 and have been separately stated in the Consolidated Statements of Income. During the three and nine months ended September 30, 2018, the Company recognized merger and acquisition integration-related recoveries in the amount of $0.8 million due to an adjustment of contract termination expenses that have been separately stated in the Consolidated Statements of Income. Supplemental Pro Forma Financial Information The following unaudited condensed pro forma information assumes the Kinderhook acquisitions had been completed as of January 1, 2018 for the three and nine months ended September 30, 2018 and September 30, 2019. The pro forma information does not include amounts related to the two acquisitions completed by CISI in 2019 The pro forma information set forth below reflects the historical results of Kinderhook combined with the Company’s consolidated statement of income with adjustments related to (a) certain purchase accounting fair value adjustments and (b) amortization of customer lists and core deposit intangibles. Acquisition-related expenses totaling $6.1 million and $7.8 million for the three and nine months ended September 30, 2019 were included in the pro forma information as if they were incurred in the first quarter of 2018. Pro Forma (Unaudited) Three Months Ended Pro Forma (Unaudited) Nine Months Ended (000’s omitted) September 30, 2019 September 30, 2018 September 30, 2019 September 30, 2018 Total revenue, net of interest expense $ 149,087 $ 148,152 $ 452,995 $ 446,084 Net income 44,154 44,313 135,370 125,505

ACCOUNTING POLICIES

ACCOUNTING POLICIES	9 Months Ended
	Sep. 30, 2019
ACCOUNTING POLICIES [Abstract]
ACCOUNTING POLICIES	NOTE C: ACCOUNTING POLICIES The accounting policies of the Company, as applied in the consolidated interim financial statements presented herein, are substantially the same as those followed on an annual basis as presented on pages 65 through 75 of the Annual Report on Form 10-K for the year ended December 31, 2018 filed with the Securities and Exchange Commission (“SEC”) on March 1, 2019 except as noted below. Contract Balances A contract asset balance occurs when an entity performs a service for a customer before the customer pays consideration (resulting in a contract receivable) or before payment is due (resulting in a contract asset). 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 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, 2019, $28.0 million of accounts receivable, including $8.3 million of unbilled fee revenue, and $1.9 million of unearned revenue was recorded in the consolidated statements of condition. As of December 31, 2018, $26.4 million of accounts receivable, including $7.8 million of unbilled fee revenue, and $2.2 million of unearned revenue was recorded in the consolidated statements of condition. Leases The Company occupies certain offices and uses certain equipment under non-cancelable operating lease agreements. The Company determines if an arrangement is a lease at inception. The right-of-use assets associated with operating leases are recorded in premises and equipment in the Company’s consolidated statements of condition. The lease liabilities associated with operating leases are included in accrued interest and other liabilities in the Company’s consolidated statements of condition. Right-of-use assets represent the Company’s right to use the underlying assets for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the associated leases. Operating lease right-of-use assets and liabilities are recognized at the commencement date of the lease based on the present value of lease payments over the lease term. The Company uses interest rates on advances from the Federal Home Loan Bank of New York available at the time of commencement to determine the present value of lease payments. The operating lease right-of-use assets include any lease payments made at the time of commencement and exclude lease incentives. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the option will be exercised. Lease expense is recognized on a straight-line basis over the lease term and is included in occupancy and equipment expense in the Company’s consolidated statements of income. The Company elected to account for lease and non-lease components separately, applies a portfolio approach to account for the lease right-of-use assets and liabilities for certain equipment leases and elected to exclude leases with a term of 12 months or less from the recognition and measurement policies described above. Derivative Financial Instruments and Hedging Activities The Company accounts for derivative financial instruments at fair value. If certain conditions are met, a derivative may be specifically designated as (1) a hedge of the exposure to changes in the fair value of a recognized asset or liability or an unrecognized firm commitment (“fair value hedge”), (2) a hedge of the exposure to variable cash flows of a forecasted transaction or the variability of cash flows to be received or paid related to a recognized asset or liability (“cash flow hedge”), or (3) an instrument with no hedging designation (“stand-alone derivative”). For a fair value hedge, the gain or loss on the derivative, as well as the offsetting loss or gain on the hedged item, are recognized in current earnings as fair values change. For a cash flow hedge, the gain or loss on the derivative is reported in other comprehensive income and is reclassified into earnings in the same periods during which the hedged transaction affects earnings. Changes in the fair value of derivatives that do not qualify for hedge accounting are reported currently in earnings, as noninterest revenues. Net cash settlements on derivatives that qualify for hedge accounting are recorded in interest income or interest expense, based on the item being hedged. Net cash settlements on derivatives that do not qualify for hedge accounting are reported in noninterest revenues. Cash flows on hedges are classified in the consolidated statements of cash flow statement the same as the cash flows of the items being hedged. The Company formally documents the relationship between derivatives and hedged items, as well as the risk-management objective and strategy for undertaking hedge transactions at the inception of the hedging relationship. This documentation includes linking the fair value or cash flow hedges to specific assets and liabilities on the statements of condition or to specific commitments or forecasted transactions. When hedge accounting is discontinued, subsequent changes in fair value of the derivative are recorded in noninterest revenues. When a fair value hedge is discontinued, the hedged asset or liability is no longer adjusted for changes in fair value and the existing basis adjustment is amortized or accreted over the remaining life of the asset or liability. When a cash flow hedge is discontinued, but the hedged cash flows or forecasted transactions are still expected to occur, gains or losses that were accumulated in other comprehensive income are amortized into earnings over the same periods which the hedged transactions will affect earnings. Recently Adopted Accounting Pronouncements In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) Topic 840, Leases In August 2017, the FASB issued ASU No. 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities. New Accounting Pronouncements In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments – Credit Losses (Topic 326) The Company is currently evaluating the impact CECL will have on the Company’s consolidated financial statements, and expects a change in the allowance for loan losses resulting from the change to expected losses for the estimated life of the financial asset. Management has developed its CECL model for the Company’s loan portfolio, which utilizes its historical data through September 30, 2019, as well as current and expected economic conditions and forecasts. The Company has completed the evaluation of its data requirements, determined its loan segments, determined the model construct for each segment, developed its qualitative framework and produced an estimated Allowance for Credit Loss amount based on the September 30, 2019 data inputs, assumptions and mathematical calculations. The Company is in the process of evaluating the model’s sensitivity to various model inputs, as well as identifying the key controls around model development, quarterly model operations and the production of quarterly and annual financial statement disclosures. Based on the preliminary September model results, the Company believes it will establish an Allowance for Credit Losses at the time of adoption of between and . This compares to an allowance for loan losses of at September based on the current incurred loss model and represents approximately a to increase in the Company’s allowance. These results should be considered preliminary and may change due to factors including, but not limited to, changes in estimated historical losses, changes in the Company’s asset quality trends, changes in current economic conditions and changes in the Company’s economic forecast. Upon adoption, the Company does not expect to record any material allowance for credit losses on its available-for-sale debt securities or on its other instruments carried at amortized cost, other than its held-for-investment loan portfolio. The Company’s regulators will permit financial institutions to “phase-in” the impact of CECL on its regulatory capital ratios over years with transitional relief of incremental capital requirements. The Company does not expect to utilize the phased-in approach and instead anticipates it will record the entire cumulative-effect adjustment against its regulatory capital at the time of adoption. In January 2017, the FASB issued ASU No. 2017-04, Intangibles-Goodwill and Other (Topic 350)

INVESTMENT SECURITIES

INVESTMENT SECURITIES	9 Months Ended
	Sep. 30, 2019
INVESTMENT SECURITIES [Abstract]
INVESTMENT SECURITIES	NOTE D: INVESTMENT SECURITIES The amortized cost and estimated fair value of investment securities as of September 30, 2019 and December 31, 2018 are as follows: September 30, 2019 December 31, 2018 (000's omitted) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Available-for-Sale Portfolio: U.S. Treasury and agency securities $ 1,482,739 $ 24,122 $ 214 $ 1,506,647 $ 2,036,474 $ 2,190 $ 14,911 $ 2,023,753 Obligations of state and political subdivisions 442,942 15,159 11 458,090 453,640 6,563 1,049 459,154 Government agency mortgage-backed securities 406,329 6,330 843 411,816 390,234 1,526 9,283 382,477 Corporate debt securities 2,542 0 2 2,540 2,588 0 42 2,546 Government agency collateralized mortgage obligations 57,452 592 35 58,009 69,342 60 1,283 68,119 Total available-for-sale portfolio $ 2,392,004 $ 46,203 $ 1,105 $ 2,437,102 $ 2,952,278 $ 10,339 $ 26,568 $ 2,936,049 Equity and other Securities: Equity securities, at fair value $ 251 $ 210 $ 0 $ 461 $ 251 $ 200 $ 19 $ 432 Federal Home Loan Bank common stock 6,912 0 0 6,912 8,768 0 0 8,768 Federal Reserve Bank common stock 31,992 0 0 31,992 30,690 0 0 30,690 Other equity securities, at adjusted cost 4,525 750 0 5,275 4,969 750 0 5,719 Total equity and other securities $ 43,680 $ 960 $ 0 $ 44,640 $ 44,678 $ 950 $ 19 $ 45,609 A summary of investment securities that have been in a continuous unrealized loss position is as follows: As of September 30, 2019 Less than 12 Months 12 Months or Longer Total (000's omitted) # Fair Value Gross Unrealized Losses # Fair Value Gross Unrealized Losses # Fair Value Gross Unrealized Losses Available-for-Sale Portfolio: U.S. Treasury and agency securities 6 $ 77,332 $ 58 12 $ 107,840 $ 156 18 $ 185,172 $ 214 Obligations of state and political subdivisions 73 7,125 11 0 0 0 73 7,125 11 Government agency mortgage-backed securities 24 34,660 95 55 58,473 748 79 93,133 843 Corporate debt securities 0 0 0 1 2,540 2 1 2,540 2 Government agency collateralized mortgage obligations 5 6,662 9 7 5,357 26 12 12,019 35 Total available-for-sale investment portfolio 108 $ 125,779 $ 173 75 $ 174,210 $ 932 183 $ 299,989 $ 1,105 As of December 31, 2018 Less than 12 Months 12 Months or Longer Total (000's omitted) # Fair Value Gross Unrealized Losses # Fair Value Gross Unrealized Losses # Fair Value Gross Unrealized Losses Available-for-Sale Portfolio: U.S. Treasury and agency securities 7 $ 473,082 $ 682 64 $ 1,213,276 $ 14,229 71 $ 1,686,358 $ 14,911 Obligations of state and political subdivisions 118 55,671 216 97 51,753 833 215 107,424 1,049 Government agency mortgage-backed securities 43 47,708 258 181 253,931 9,025 224 301,639 9,283 Corporate debt securities 0 0 0 1 2,546 42 1 2,546 42 Government agency collateralized mortgage obligations 1 66 0 41 63,112 1,283 42 63,178 1,283 Total available-for-sale investment portfolio 169 $ 576,527 $ 1,156 384 $ 1,584,618 $ 25,412 553 $ 2,161,145 $ 26,568 Equity and other Securities: Equity securities, at fair value 1 $ 82 $ 19 0 $ 0 $ 0 1 $ 82 $ 19 Total equity and other securities 1 $ 82 $ 19 0 $ 0 $ 0 1 $ 82 $ 19 The unrealized losses reported pertaining to securities issued by the U.S. government and its sponsored entities, include treasuries, agencies, and mortgage-backed securities issued by Ginnie Mae, Fannie Mae, and Freddie Mac, which are currently rated AAA by Moody’s Investor Services, AA+ by Standard & Poor’s and are guaranteed by the U.S. government. The majority of the obligations of state and political subdivisions and corporations carry a credit rating of A or better. Additionally, a majority of the obligations of state and political subdivisions carry a secondary level of credit enhancement. The Company does not intend to sell these securities, nor is it more likely than not that the Company will be required to sell these securities prior to recovery of the amortized cost. The unrealized losses in the portfolios are primarily attributable to changes in interest rates. As such, management does not believe any individual unrealized loss as of September 30, 2019 represents other-than-temporary impairment. The amortized cost and estimated fair value of debt securities at September 30, 2019, by contractual maturity, are shown below. Expected maturities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. Securities not due at a single maturity date are shown separately. Available-for-Sale (000's omitted) Amortized Cost Fair Value Due in one year or less $ 71,512 $ 71,510 Due after one through five years 1,512,018 1,538,064 Due after five years through ten years 54,176 58,251 Due after ten years 290,517 299,452 Subtotal 1,928,223 1,967,277 Government agency mortgage-backed securities 406,329 411,816 Government agency collateralized mortgage obligations 57,452 58,009 Total $ 2,392,004 $ 2,437,102 As of September 30, 2019, $245.6 million of U.S. Treasury securities were pledged as collateral for securities sold under agreement to repurchase. All securities sold under agreement to repurchase as of September 30, 2019 have an overnight and continuous maturity. During the nine-month period ending 30, 2019, the Company sold $ million of U.S. Treasury and agency securities, recognizing $ million of gross realized gains and $ million of gross realized losses. The proceeds from these sales were primarily held in interest-earning cash and cash equivalents at higher net yields as of S 30, 2019.

LOANS

LOANS	9 Months Ended
	Sep. 30, 2019
LOANS [Abstract]
LOANS	NOTE E: LOANS The segments of the Company’s loan portfolio are disaggregated into the following classes that allow management to monitor risk and performance: • Consumer mortgages consist primarily of fixed rate residential instruments, typically 10 – 30 years in contractual term, secured by first liens on real property. • Business lending is comprised of general purpose commercial and industrial loans including, but not limited to, municipal lending, agricultural-related and dealer floor plans, as well as mortgages on commercial properties. • Consumer indirect consists primarily of installment loans originated through selected dealerships and are secured by automobiles, marine and other recreational vehicles. • Consumer direct consists of all other loans to consumers such as personal installment loans and lines of credit. • Home equity products are consumer purpose installment loans or lines of credit most often secured by a first or second lien position on residential real estate with terms up to 30 years. The balances of these classes are summarized as follows: (000's omitted) September 30, 2019 December 31, 2018 Business lending $ 2,779,612 $ 2,396,977 Consumer mortgage 2,405,191 2,235,408 Consumer indirect 1,091,980 1,083,207 Consumer direct 187,379 178,820 Home equity 389,029 386,709 Gross loans, including deferred origination costs 6,853,191 6,281,121 Allowance for loan losses (49,423 ) (49,284 ) Loans, net of allowance for loan losses $ 6,803,768 $ 6,231,837 The outstanding balance related to credit impaired acquired loans was $16.7 million and $7.4 million at September 30, 2019 and December 31, 2018, respectively. The changes in the accretable discount related to the credit impaired acquired loans are as follows: (000’s omitted) Balance at December 31, 2018 $ 437 Accretion recognized, year-to-date (302 ) Net reclassification from non-accretable to accretable 96 Kinderhook acquisition 512 Balance at September 30, 2019 $ 743 Credit Quality Management monitors the credit quality of its loan portfolio on an ongoing basis. Measurement of delinquency and past due status are based on the contractual terms of each loan. Past due loans are reviewed on a monthly basis to identify loans for non-accrual status. The following is an aged analysis of the Company’s past due loans, by class as of September 30, 2019: Legacy Loans (excludes loans acquired after January 1, 2009) (000’s omitted) Past Due 30 – 89 Days 90+ Days Past Due and Still Accruing Nonaccrual Total Past Due Current Total Loans Business lending $ 2,697 $ 189 $ 4,590 $ 7,476 $ 1,778,596 $ 1,786,072 Consumer mortgage 11,038 2,976 10,650 24,664 1,921,265 1,945,929 Consumer indirect 10,307 177 0 10,484 1,074,849 1,085,333 Consumer direct 1,046 38 0 1,084 177,242 178,326 Home equity 1,496 354 1,404 3,254 308,375 311,629 Total $ 26,584 $ 3,734 $ 16,644 $ 46,962 $ 5,260,327 $ 5,307,289 Acquired Loans (000’s omitted) Past Due 30 – 89 Days 90+ Days Past Due and Still Accruing Nonaccrual Total Past Due Acquired Impaired (1) Current Total Loans Business lending $ 747 $ 997 $ 3,957 $ 5,701 $ 11,508 $ 976,331 $ 993,540 Consumer mortgage 1,573 171 2,409 4,153 0 455,109 459,262 Consumer indirect 33 32 0 65 0 6,582 6,647 Consumer direct 86 5 54 145 0 8,908 9,053 Home equity 279 125 546 950 0 76,450 77,400 Total $ 2,718 $ 1,330 $ 6,966 $ 11,014 $ 11,508 $ 1,523,380 $ 1,545,902 (1) Acquired impaired loans were not classified as nonperforming assets as the loans are considered to be performing under ASC 310-30. As a result interest income, through the accretion of the difference between the carrying amount of the loans and the expected cashflows, is being recognized on all acquired impaired loans. The following is an aged analysis of the Company’s past due loans by class as of December 31, 2018: Legacy Loans (000’s omitted) Past Due 30 – 89 Days 90+ Days Past Due and Still Accruing Nonaccrual Total Past Due Current Total Loans Business lending $ 5,261 $ 179 $ 4,872 $ 10,312 $ 1,608,515 $ 1,618,827 Consumer mortgage 12,468 1,393 9,872 23,733 1,824,717 1,848,450 Consumer indirect 14,609 258 0 14,867 1,057,525 1,072,392 Consumer direct 1,778 48 0 1,826 173,948 175,774 Home equity 983 228 1,438 2,649 309,892 312,541 Total $ 35,099 $ 2,106 $ 16,182 $ 53,387 $ 4,974,597 $ 5,027,984 Acquired Loans (000’s omitted) Past Due 30 – 89 Days 90+ Days Past Due and Still Accruing Nonaccrual Total Past Due Acquired Impaired (1) Current Total Loans Business lending $ 974 $ 0 $ 3,498 $ 4,472 $ 5,446 $ 768,232 $ 778,150 Consumer mortgage 841 232 2,390 3,463 0 383,495 386,958 Consumer indirect 78 34 0 112 0 10,703 10,815 Consumer direct 115 4 0 119 0 2,927 3,046 Home equity 613 79 474 1,166 0 73,002 74,168 Total $ 2,621 $ 349 $ 6,362 $ 9,332 $ 5,446 $ 1,238,359 $ 1,253,137 (1) Acquired impaired loans were not classified as nonperforming assets as the loans are considered to be performing under ASC 310-30. As a result interest income, through the accretion of the difference between the carrying amount of the loans and the expected cashflows, is being recognized on all acquired impaired loans. The Company uses several credit quality indicators to assess credit risk in an ongoing manner. The Company’s primary credit quality indicator for its business lending portfolio is an internal credit risk rating system that categorizes loans as “pass”, “special mention”, “classified”, or “doubtful”. Credit risk ratings are applied individually to those classes of loans that have significant or unique credit characteristics that benefit from a case-by-case evaluation. In general, the following are the definitions of the Company’s credit quality indicators: Pass The condition of the borrower and the performance of the loans are satisfactory or better. Special Mention The condition of the borrower has deteriorated although the loan performs as agreed. Classified The condition of the borrower has significantly deteriorated and the performance of the loan could further deteriorate, if deficiencies are not corrected. Doubtful The condition of the borrower has deteriorated to the point that collection of the balance is improbable based on current facts and conditions. The following table shows the amount of business lending loans by credit quality category: September 30, 2019 December 31, 2018 (000’s omitted) Legacy Acquired Total Legacy Acquired Total Pass $ 1,609,382 $ 886,363 $ 2,495,745 $ 1,439,337 $ 702,493 $ 2,141,830 Special mention 91,159 61,289 152,448 105,065 40,107 145,172 Classified 85,531 34,380 119,911 74,425 28,525 102,950 Doubtful 0 0 0 0 1,579 1,579 Acquired impaired 0 11,508 11,508 0 5,446 5,446 Total $ 1,786,072 $ 993,540 $ 2,779,612 $ 1,618,827 $ 778,150 $ 2,396,977 All other loans are underwritten and structured using standardized criteria and characteristics, primarily payment performance, and are normally risk rated and monitored collectively on a monthly basis. These are typically loans to individuals in the consumer categories and are delineated as either performing or nonperforming. Performing loans include loans classified as current as well as those classified as 30 - 89 days past due. Nonperforming loans include 90+ days past due and still accruing and nonaccrual loans. The following table details the balances in all other loan categories at September 30, 2019: Legacy Loans (000’s omitted) Consumer Mortgage Consumer Indirect Consumer Direct Home Equity Total Performing $ 1,932,303 $ 1,085,156 $ 178,288 $ 309,871 $ 3,505,618 Nonperforming 13,626 177 38 1,758 15,599 Total $ 1,945,929 $ 1,085,333 $ 178,326 $ 311,629 $ 3,521,217 Acquired Loans (000’s omitted) Consumer Mortgage Consumer Indirect Consumer Direct Home Equity Total Performing $ 456,682 $ 6,615 $ 8,994 $ 76,729 $ 549,020 Nonperforming 2,580 32 59 671 3,342 Total $ 459,262 $ 6,647 $ 9,053 $ 77,400 $ 552,362 The following table details the balances in all other loan categories at December 31, 2018: Legacy Loans (000’s omitted) Consumer Mortgage Consumer Indirect Consumer Direct Home Equity Total Performing $ 1,837,185 $ 1,072,134 $ 175,726 $ 310,875 $ 3,395,920 Nonperforming 11,265 258 48 1,666 13,237 Total $ 1,848,450 $ 1,072,392 $ 175,774 $ 312,541 $ 3,409,157 Acquired Loans (000’s omitted) Consumer Mortgage Consumer Indirect Consumer Direct Home Equity Total Performing $ 384,336 $ 10,781 $ 3,042 $ 73,615 $ 471,774 Nonperforming 2,622 34 4 553 3,213 Total $ 386,958 $ 10,815 $ 3,046 $ 74,168 $ 474,987 All loan classes are collectively evaluated for impairment except business lending. A summary of individually evaluated impaired loans as of September 30, 2019 and December 31, 2018 follows: (000’s omitted) September 30, 2019 December 31, 2018 Loans with allowance allocation $ 0 $ 3,956 Loans without allowance allocation 5,172 2,230 Carrying balance 5,172 6,186 Contractual balance 11,896 12,078 Specifically allocated allowance 0 956 In the course of working with borrowers, the Company may choose to restructure the contractual terms of certain loans. In this scenario, the Company attempts to work-out an alternative payment schedule with the borrower in order to optimize collectability of the loan. Any loans that are modified are reviewed by the Company to identify if a troubled debt restructuring (“TDR”) has occurred, which is when, for economic or legal reasons related to a borrower’s financial difficulties, the Company grants a concession to the borrower that it would not otherwise consider. Terms may be modified to fit the ability of the borrower to repay in line with its current financial standing and the restructuring of the loan may include the transfer of assets from the borrower to satisfy the debt, a modification of loan terms, or a combination of the two. In accordance with the clarified guidance issued by the Office of the Comptroller of the Currency (“OCC”), consumer mortgage loans that have been discharged in Chapter 7 bankruptcy but not reaffirmed by the borrower, are classified as TDRs, irrespective of payment history or delinquency status, even if the repayment terms for the loan have not been otherwise modified. The Company’s lien position against the underlying collateral remains unchanged. Pursuant to that guidance, the Company records a charge-off equal to any portion of the carrying value that exceeds the net realizable value of the collateral. The amount of loss incurred in the three and nine months ended September 30, 2019 and 2018 was immaterial. TDRs that are less than $0.5 million are collectively included in the general loan loss allocation and the qualitative review. TDRs that are commercial loans and greater than $0.5 million are individually evaluated for impairment, and if necessary, a specific allocation of the allowance for loan losses is provided. As a result, the determination of the amount of allowance for loan losses related to TDRs is the same as detailed in the critical accounting policies. Information regarding TDRs as of September 30, 2019 and December 31, 2018 is as follows: September 30, 2019 December 31, 2018 (000’s omitted) Nonaccrual Accruing Total Nonaccrual Accruing Total # Amount # Amount # Amount # Amount # Amount # Amount Business lending 5 $ 662 3 $ 205 8 $ 867 4 $ 162 2 $ 165 6 $ 327 Consumer mortgage 57 2,527 49 1,945 106 4,472 46 1,986 46 1,769 92 3,755 Consumer indirect 0 0 77 854 77 854 0 0 77 857 77 857 Consumer direct 0 0 22 91 22 91 0 0 22 71 22 71 Home equity 13 230 11 310 24 540 12 240 9 275 21 515 Total 75 $ 3,419 162 $ 3,405 237 $ 6,824 62 $ 2,388 156 $ 3,137 218 $ 5,525 The following table presents information related to loans modified in a TDR during the three months and nine months ended September 30, 2019 and 2018. Of the loans noted in the table below, all consumer mortgage loans for the three months and nine months ended September 30, 2019 and 2018 were modified due to a Chapter 7 bankruptcy as described previously. The financial effects of these restructurings were immaterial. Three Months Ended September 30, 2019 Three Months Ended September 30, 2018 (000’s omitted) Number of loans modified Outstanding Balance Number of loans modified Outstanding Balance Business lending 1 $ 415 0 $ 0 Consumer mortgage 8 464 4 195 Consumer indirect 10 116 14 117 Consumer direct 2 25 2 10 Home equity 0 0 1 0 Total 21 $ 1,020 21 $ 322 Nine Months Ended September 30, 2019 Nine Months Ended September 30, 2018 (000’s omitted) Number of loans modified Outstanding Balance Number of loans modified Outstanding Balance Business lending 3 $ 660 1 $ 93 Consumer mortgage 19 1,271 7 407 Consumer indirect 22 206 24 176 Consumer direct 5 35 5 21 Home equity 4 72 2 85 Total 53 $ 2,244 39 $ 782 Allowance for Loan Losses The allowance for loan losses is general in nature and is available to absorb losses from any loan type despite the analysis below. The following presents by class the activity in the allowance for loan losses: Three Months Ended September 30, 2019 (000’s omitted) Business Lending Consumer Mortgage Consumer Indirect Consumer Direct Home Equity Unallocated Acquired Impaired Total Beginning balance $ 17,769 $ 10,763 $ 14,345 $ 3,184 $ 2,103 $ 991 $ 155 $ 49,310 Charge-offs (305 ) (200 ) (2,224 ) (456 ) (45 ) 0 0 (3,230 ) Recoveries 290 8 1,095 167 32 0 0 1,592 Provision 301 (94 ) 1,221 383 (8 ) (53 ) 1 1,751 Ending balance $ 18,055 $ 10,477 $ 14,437 $ 3,278 $ 2,082 $ 938 $ 156 $ 49,423 Three Months Ended September 30, 2018 (000’s omitted) Business Lending Consumer Mortgage Consumer Indirect Consumer Direct Home Equity Unallocated Acquired Impaired Total Beginning balance $ 18,439 $ 10,473 $ 14,424 $ 3,164 $ 2,015 $ 1,070 $ 33 $ 49,618 Charge-offs (73 ) (144 ) (2,364 ) (465 ) (221 ) 0 0 (3,267 ) Recoveries 93 46 1,190 223 15 0 0 1,567 Provision 321 (205 ) 1,719 299 225 (159 ) 15 2,215 Ending balance $ 18,780 $ 10,170 $ 14,969 $ 3,221 $ 2,034 $ 911 $ 48 $ 50,133 Nine Months Ended September 30, 2019 (000’s omitted) Business Lending Consumer Mortgage Consumer Indirect Consumer Direct Home Equity Unallocated Acquired Impaired Total Beginning balance $ 18,522 $ 10,124 $ 14,366 $ 3,095 $ 2,144 $ 1,000 $ 33 $ 49,284 Charge-offs (1,774 ) (1,040 ) (5,529 ) (1,436 ) (223 ) 0 0 (10,002 ) Recoveries 593 44 3,296 567 68 0 0 4,568 Provision 714 1,349 2,304 1,052 93 (62 ) 123 5,573 Ending balance $ 18,055 $ 10,477 $ 14,437 $ 3,278 $ 2,082 $ 938 $ 156 $ 49,423 Nine Months Ended September 30, 2018 (000’s omitted) Business Lending Consumer Mortgage Consumer Indirect Consumer Direct Home Equity Unallocated Acquired Impaired Total Beginning balance $ 17,257 $ 10,465 $ 13,468 $ 3,039 $ 2,107 $ 1,100 $ 147 $ 47,583 Charge-offs (2,000 ) (588 ) (6,031 ) (1,324 ) (325 ) 0 (368 ) (10,636 ) Recoveries 404 109 3,688 612 31 0 0 4,844 Provision 3,119 184 3,844 894 221 (189 ) 269 8,342 Ending balance $ 18,780 $ 10,170 $ 14,969 $ 3,221 $ 2,034 $ 911 $ 48 $ 50,133

GOODWILL AND IDENTIFIABLE INTAN

GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS	9 Months Ended
	Sep. 30, 2019
GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS [Abstract]
GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS	NOTE F: GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS The gross carrying amount and accumulated amortization for each type of identifiable intangible asset are as follows: September 30, 2019 December 31, 2018 (000's omitted) Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Amortizing intangible assets: Core deposit intangibles $ 66,475 $ (48,603 ) $ 17,872 $ 62,902 $ (44,306 ) $ 18,596 Other intangibles 89,266 (40,063 ) 49,203 87,616 (32,366 ) 55,250 Total amortizing intangibles $ 155,741 $ (88,666 ) $ 67,075 $ 150,518 $ (76,672 ) $ 73,846 The estimated aggregate amortization expense for each of the five succeeding fiscal years ended December 31 is as follows: (000's omitted) Oct - Dec 2019 $ 3,962 2020 13,801 2021 11,786 2022 10,105 2023 8,457 Thereafter 18,964 Total $ 67,075 Shown below are the components of the Company’s goodwill at December 31, 2018 and September 30, 2019: (000’s omitted) December 31, 2018 Activity September 30, 2019 Goodwill $ 738,327 $ 40,107 $ 778,434 Accumulated impairment (4,824 ) 0 (4,824 ) Goodwill, net $ 733,503 $ 40,107 $ 773,610

LEASES

LEASES	9 Months Ended
	Sep. 30, 2019
LEASES [Abstract]
LEASES	NOTE G: LEASES The Company has operating leases for certain offices and certain equipment. These leases have remaining terms that range from less than one year to 15 years. Options to extend the leases range from a single extension option of one year to multiple extension options for up to 40 years. Certain agreements include an option to terminate the lease within one year. The components of lease expense are as follows: (000’s omitted) Three Months Ended September 30, 2019 Nine Months Ended September 30, 2019 Operating lease cost $ 2,231 $ 6,493 Variable lease cost 9 9 Short-term lease cost (1) 77 180 Total lease cost $ 2,317 $ 6,682 (1) Short-term lease cost includes the cost of leases with terms of twelve months or less, excluding leases with terms of one month or less. Supplemental cash flow information related to leases is as follows: (000’s omitted) Nine Months Ended September 30, 2019 Cash paid for amounts included in the measurement of lease liabilities: Operating cash outflows for operating leases $ 5,987 Right-of-use assets obtained in exchange for lease obligations: Operating leases 13,766 Supplemental balance sheet information related to leases is as follows: (000’s omitted, except lease term and discount rate) September 30, 2019 Operating leases Operating lease right-of-use assets $ 41,948 Operating lease liabilities 42,769 Weighted average remaining lease term Operating leases 6.7 years Weighted average discount rate Operating leases 2.95 % Maturities of lease liabilities as of September 30, 2019 are as follows: (000’s omitted) Operating Leases Oct - Dec 2019 $ 2,253 2020 9,372 2021 7,934 2022 6,645 2023 5,674 Thereafter 15,697 Total lease payments 47,575 Less imputed interest (4,806 ) Total $ 42,769 Included in the Company’s operating leases are related party leases where BPAS Actuarial & Pension Services, LLC and OneGroup NY, Inc., subsidiaries of the Company, lease office space from 706 North Clinton, LLC., an entity the Company holds a 50 % membership interest in through its subsidiary Oneida Preferred Funding II, LLC. As of September 30, 2019, the operating lease right-of-use assets and operating lease liabilities associated with these related party leases total $5.0 million and $5.0 million, respectively. As of September 30, 2019, the weighted average remaining lease term and weighted average discount rate for the Company’s related party leases are 10.2 years and 3.67 %, respectively. The maturities of the Company’s related party lease liabilities as of September 30, 2019 are as follows: (000’s omitted) 706 North Clinton, LLC Oct - Dec 2019 $ 148 2020 591 2021 591 2022 591 2023 591 Thereafter 3,538 Total lease payments 6,050 Less imputed interest (1,011 ) Total $ 5,039 As of September 30, 2019, the Company has an immaterial amount of additional operating leases for offices and equipment that have not yet commenced.

MANDATORILY REDEEMABLE PREFERRE

MANDATORILY REDEEMABLE PREFERRED SECURITIES	9 Months Ended
	Sep. 30, 2019
MANDATORILY REDEEMABLE PREFERRED SECURITIES [Abstract]
MANDATORILY REDEEMABLE PREFERRED SECURITIES	NOTE H: MANDATORILY REDEEMABLE PREFERRED SECURITIES As of September the Company sponsors business trust, Community Capital Trust IV (“CCT IV”), of which of the common stock is owned by the Company. The Company previously sponsored MBVT Statutory Trust I (“MBVT I”) and Kinderhook Capital Trust (“KCT”) until September when the Company exercised its right to redeem all of the MBVT I and KCT debentures and associated preferred securities for a total of and , respectively. The common stock of MBVT Statutory Trust I was acquired in the Merchants Bancshares, Inc. (“Merchants”) acquisition and the common stock of Kinderhook Capital Trust was acquired in the Kinderhook Bank Corp. (“Kinderhook”) acquisition. The trusts were formed for the purpose of issuing company-obligated mandatorily redeemable preferred securities to -party investors and investing the proceeds from the sale of such preferred securities solely in junior subordinated debt securities of the Company. The debentures held by each trust are the sole assets of such trust. Distributions on the preferred securities issued by each trust are payable quarterly at a rate per annum equal to the interest rate being earned by the trust on the debentures held by that trust and are recorded as interest expense in the consolidated financial statements. The preferred securities are subject to mandatory redemption, in whole or in part, upon repayment of the debentures. The Company has entered into agreements which, taken collectively, fully and unconditionally guarantee the preferred securities subject to the terms of each of the guarantees. As of September 30, 2019, the terms of the preferred securities of CCT IV are as follows: Issuance Par Maturity Trust Date Amount Interest Rate Date Call Price CCT IV 12/8/2006 $75.0 million 3 month LIBOR plus 1.65% (3.77%) 12/15/2036 Par

BENEFIT PLANS

BENEFIT PLANS	9 Months Ended
	Sep. 30, 2019
BENEFIT PLANS [Abstract]
BENEFIT PLANS	NOTE I: BENEFIT PLANS The Company provides a qualified defined benefit pension to eligible employees and retirees, other post-retirement health and life insurance benefits to certain retirees, an unfunded supplemental pension plan for certain key executives, and an unfunded stock balance plan for certain of its nonemployee directors. The Company accrues for the estimated cost of these benefits through charges to expense during the years that employees earn these benefits. The service cost component of net periodic benefit income is included in the salaries and employee benefits line of the Consolidated Statements of Income, while the other components of net periodic benefit income are included in other expenses. The Company made a $7.3 million contribution to its defined benefit pension plan in the first quarter of 2019. Effective June 1, 2018, the Company adopted the Community Bank System, Inc. Restoration Plan (“Restoration Plan”). The Restoration Plan is a non-qualified deferred compensation plan for certain employees whose benefits under tax-qualified retirement plans are restricted by the Internal Revenue Code Section 401(a)(17) limitation on compensation. Adoption of the plan resulted in an unfunded initial projected benefit obligation of approximately $0.8 million that will be amortized over the average expected future years of service of active plan participants. The net periodic benefit cost for the three and nine months ended September 30, 2019 and 2018 is as follows: Pension Benefits Post-retirement Benefits Three Months Ended Nine Months Ended Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, (000's omitted) 2019 2018 2019 2018 2019 2018 2019 2018 Service cost $ 1,270 $ 1,154 $ 3,811 $ 3,396 $ 0 $ 0 $ 0 $ 0 Interest cost 1,566 1,422 4,698 4,251 18 18 53 52 Expected return on plan assets (3,578 ) (3,705 ) (10,733 ) (11,115 ) 0 0 0 0 Amortization of unrecognized net loss 642 299 1,926 895 9 5 28 15 Amortization of prior service cost 17 (60 ) 48 (225 ) (45 ) (45 ) (134 ) (134 ) Net periodic benefit $ (83 ) $ (890 ) $ (250 ) $ (2,798 ) $ (18 ) $ (22 ) $ (53 ) $ (67 )

EARNINGS PER SHARE

EARNINGS PER SHARE	9 Months Ended
	Sep. 30, 2019
EARNINGS PER SHARE [Abstract]
EARNINGS PER SHARE	NOTE J: EARNINGS PER SHARE The two class method is used in the calculations of basic and diluted earnings per share. Under the two class method, earnings available to common shareholders for the period are allocated between common shareholders and participating securities according to dividends declared and participation rights in undistributed earnings. The Company has determined that all of its outstanding non-vested stock awards are participating securities as of September 30, 2019. Basic earnings per share are computed based on the weighted-average of the common shares outstanding for the period. Diluted earnings per share are based on the weighted-average of the shares outstanding and the assumed exercise of stock options during the year. The dilutive effect of options is calculated using the treasury stock method of accounting. The treasury stock method determines the number of common shares that would be outstanding if all the dilutive options (those where the average market price is greater than the exercise price) were exercised and the proceeds were used to repurchase common shares in the open market at the average market price for the applicable time period. There were approximately 0.5 million weighted-average anti-dilutive stock options outstanding for the three months and nine months ended September 30, 2019, compared to 0.4 million weighted-average anti-dilutive stock options outstanding for the three months and nine months ended September 30, 2018 that were not included in the computation below. The following is a reconciliation of basic to diluted earnings per share for the three and nine months ended September 30, 2019 and 2018: Three Months Ended Nine Months Ended September 30, September 30, (000's omitted, except per share data) 2019 2018 2019 2018 Net income $ 39,218 $ 43,106 $ 126,179 $ 127,818 Income attributable to unvested stock-based compensation awards (102 ) (191 ) (331 ) (563 ) Income available to common shareholders $ 39,116 $ 42,915 $ 125,848 $ 127,255 Weighted-average common shares outstanding – basic 51,750 51,250 51,644 51,108 Basic earnings per share $ 0.76 $ 0.84 $ 2.44 $ 2.49 Net income $ 39,218 $ 43,106 $ 126,179 $ 127,818 Income attributable to unvested stock-based compensation awards (102 ) (191 ) (331 ) (563 ) Income available to common shareholders $ 39,116 $ 42,915 $ 125,848 $ 127,255 Weighted-average common shares outstanding – basic 51,750 51,250 51,644 51,108 Assumed exercise of stock options 496 608 522 590 Weighted-average common shares outstanding – diluted 52,246 51,858 52,166 51,698 Diluted earnings per share $ 0.75 $ 0.83 $ 2.41 $ 2.46 Stock Repurchase Program At its December 2017 meeting, the Company’s Board of Directors (the “Board”) approved a stock repurchase program authorizing the repurchase of up to 2.5 million shares of the Company’s common stock in accordance with securities laws and regulations, through December 31, 2018. At its December 2018 meeting, the Board approved a similar program for 2019, authorizing the repurchase of up to 2.5 million shares of the Company’s common stock through December 31, 2019. Any repurchased shares will be used for general corporate purposes, including those related to stock plan activities. The timing and extent of repurchases will depend on market conditions and other corporate considerations as determined at the Company’s discretion. The Company did not repurchase any shares under the authorized plan during the first nine months of 2019 or 2018.

COMMITMENTS, CONTINGENT LIABILI

COMMITMENTS, CONTINGENT LIABILITIES AND RESTRICTIONS	9 Months Ended
	Sep. 30, 2019
COMMITMENTS, CONTINGENT LIABILITIES AND RESTRICTIONS [Abstract]
COMMITMENTS, CONTINGENT LIABILITIES AND RESTRICTIONS	NOTE K: COMMITMENTS, CONTINGENT LIABILITIES AND RESTRICTIONS 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 consist primarily of commitments to extend credit and standby letters of credit. Commitments to extend credit are agreements to lend to customers, generally having fixed expiration dates or other termination clauses that may require payment of a fee. These commitments consist principally of unused commercial and consumer credit lines. Standby letters of credit generally are contingent upon the failure of the customer to perform according to the terms of an underlying contract with a third party. The credit risks associated with commitments to extend credit and standby letters of credit are essentially the same as that involved with extending loans to customers and are subject to the Company’s normal credit policies. Collateral may be obtained based on management’s assessment of the customer’s creditworthiness. The fair value of the standby letters of credit is immaterial for disclosure. The contract amounts of commitments and contingencies are as follows: (000's omitted) September 30, 2019 December 31, 2018 Commitments to extend credit $ 1,065,127 $ 1,134,576 Standby letters of credit 37,968 33,169 Total $ 1,103,095 $ 1,167,745 The Company and its subsidiaries are subject in the normal course of business to various pending and threatened legal proceedings in which claims for monetary damages are asserted. As of September 30, 2019, management, after consultation with legal counsel, does not anticipate that the aggregate ultimate liability arising out of litigation pending or threatened against the Company or its subsidiaries will be material to the Company’s consolidated financial position. On at least a quarterly basis, the Company assesses its liabilities and contingencies in connection with such legal proceedings. For those matters where it is probable that the Company will incur losses and the amounts of the losses can be reasonably estimated, the Company records an expense and corresponding liability in its consolidated financial statements. To the extent the pending or threatened litigation could result in exposure in excess of that liability, the amount of such excess is not currently estimable. The range of reasonably possible losses for matters where an exposure is not currently estimable or considered probable, beyond the existing recorded liabilities, is believed to be between $0 and $1 million in the aggregate. Although the Company does not believe that the outcome of pending litigation will be material to the Company’s consolidated financial position, it cannot rule out the possibility that such outcomes will be material to the consolidated results of operations for a particular reporting period in the future.

FAIR VALUE

FAIR VALUE	9 Months Ended
	Sep. 30, 2019
FAIR VALUE [Abstract]
FAIR VALUE	NOTE L: FAIR VALUE Accounting standards establish a framework for measuring fair value and require certain disclosures about such fair value instruments. It defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (i.e. exit price). Inputs used to measure fair value are classified into the following hierarchy: • Level 1 - Quoted prices in active markets for identical assets or liabilities. • Level 2 - Quoted prices in active markets for similar assets or liabilities, or quoted prices for identical or similar assets or liabilities in markets that are not active, or inputs other than quoted prices that are observable for the asset or liability. • Level 3 - Significant valuation assumptions not readily observable in a market. A financial instrument’s categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement. The following tables set forth the Company’s financial assets and liabilities that were accounted for at fair value on a recurring basis. There were no transfers between any of the levels for the periods presented. September 30, 2019 (000's omitted) Level 1 Level 2 Level 3 Total Fair Value Available-for-sale investment securities: U.S. Treasury and agency securities $ 1,343,370 $ 163,277 $ 0 $ 1,506,647 Obligations of state and political subdivisions 0 458,090 0 458,090 Government agency mortgage-backed securities 0 411,816 0 411,816 Corporate debt securities 0 2,540 0 2,540 Government agency collateralized mortgage obligations 0 58,009 0 58,009 Total available-for-sale investment securities 1,343,370 1,093,732 0 2,437,102 Equity securities 461 0 0 461 Interest rate swap agreements asset 0 1,095 0 1,095 Interest rate swap agreements liability 0 (748 ) 0 (748 ) Total $ 1,343,831 $ 1,094,079 $ 0 $ 2,437,910 December 31, 2018 (000's omitted) Level 1 Level 2 Level 3 Total Fair Value Available-for-sale investment securities: U.S. Treasury and agency securities $ 1,896,931 $ 126,822 $ 0 $ 2,023,753 Obligations of state and political subdivisions 0 459,154 0 459,154 Government agency mortgage-backed securities 0 382,477 0 382,477 Corporate debt securities 0 2,546 0 2,546 Government agency collateralized mortgage obligations 0 68,119 0 68,119 Total available-for-sale investment securities 1,896,931 1,039,118 0 2,936,049 Equity securities 432 0 0 432 Mortgage loans held for sale 0 83 0 83 Interest rate swap agreements asset 0 793 0 793 Interest rate swap agreements liability 0 (742 ) 0 (742 ) Total $ 1,897,363 $ 1,039,252 $ 0 $ 2,936,615 The valuation techniques used to measure fair value for the items in the table above are as follows: • Available-for-sale investment securities and equity securities – The fair values of available-for-sale investment securities are based upon quoted prices, if available. If quoted prices are not available, fair values are measured using quoted market prices for similar securities or model-based valuation techniques. Level 1 securities include U.S. Treasury obligations and marketable equity securities that are traded by dealers or brokers in active over-the-counter markets. Level 2 securities include U.S. agency securities, mortgage-backed securities issued by government-sponsored entities, municipal securities and corporate debt securities that are valued by reference to prices for similar securities or through model-based techniques in which all significant inputs, such as reported trades, trade execution data, LIBOR swap yield curve, market prepayment speeds, credit information, market spreads, and security’s terms and conditions, are observable. See Note D for further disclosure of the fair value of investment securities. • Mortgage loans held for sale – The Company has elected to value loans held for sale at fair value in order to more closely match the gains and losses associated with loans held for sale with the gains and losses on forward sales contracts. Accordingly, the impact on the valuation will be recognized in the Company’s consolidated statement of income. All mortgage loans held for sale are current and in performing status. The fair value of mortgage loans held for sale is determined using quoted secondary-market prices of loans with similar characteristics and, as such, has been classified as a Level 2 valuation. There were no mortgage loans held for sale at September 30, 2019. The unpaid principal value of mortgage loans held for sale was approximately $0.1 million at December 31, 2018. The unrealized gain on mortgage loans held for sale was recognized in other banking revenues in the consolidated statements of income and is immaterial. • Forward sales commitments – The Company enters into forward sales commitments to sell certain residential real estate loans. Such commitments are considered to be derivative financial instruments and, therefore, are carried at estimated fair value in the other asset or other liability section of the consolidated statement of condition. The fair value of these forward sales commitments is primarily measured by obtaining pricing from certain government-sponsored entities and reflects the underlying price the entity would pay the Company for an immediate sale on these mortgages. As such, these instruments are classified as Level 2 in the fair value hierarchy. • Commitments to originate real estate loans for sale – The Company enters into various commitments to originate residential real estate loans for sale. Such commitments are considered to be derivative financial instruments and, therefore, are carried at estimated fair value in the other asset or other liability section of the consolidated statement of condition. The estimated fair value of these commitments is determined using quoted secondary market prices obtained from certain government-sponsored entities. Additionally, accounting guidance requires the expected net future cash flows related to the associated servicing of the loan to be included in the fair value measurement of the derivative. The expected net future cash flows are based on a valuation model that calculates the present value of estimated net servicing income. The valuation model incorporates assumptions that market participants would use in estimating future net servicing income. Such assumptions include estimates of the cost of servicing loans, appropriate discount rate and prepayment speeds. The determination of expected net cash flows is considered a significant unobservable input contributing to the Level 3 classification of commitments to originate real estate loans for sale. • Interest rate swaps – The interest rate swaps are reported at their fair value utilizing Level 2 inputs from third parties. The fair value of the interest rate swaps are determined using prices obtained from a third party advisor. The fair value measurement of the interest rate swap is determined by netting the discounted future fixed cash payments and the discounted expected variable cash receipts. The variable cash receipts are based on the expectation of future interest rates derived from observed market interest rate curves. The changes in Level 3 assets measured at fair value on a recurring basis are immaterial. The fair value information of assets and liabilities measured on a non-recurring basis presented below is not as of the period-end, but rather as of the date the fair value adjustment was recorded closest to the date presented. September 30, 2019 December 31, 2018 (000's omitted) Level 1 Level 2 Level 3 Total Fair Value Level 1 Level 2 Level 3 Total Fair Value Impaired loans $ 0 $ 0 $ 1,729 $ 1,729 $ 0 $ 0 $ 1,102 $ 1,102 Mortgage servicing rights 0 0 93 93 0 0 0 0 Other real estate owned 0 0 1,258 1,258 0 0 1,320 1,320 Total $ 0 $ 0 $ 3,080 $ 3,080 $ 0 $ 0 $ 2,422 $ 2,422 Loans are generally not recorded at fair value on a recurring basis. Periodically, the Company records nonrecurring adjustments to the carrying value of loans based on fair value measurements for partial charge-offs of the uncollectible portions of those loans. Nonrecurring adjustments also include certain impairment amounts for collateral-dependent loans calculated when establishing the allowance for loan losses. Such amounts are generally based on the fair value of the underlying collateral supporting the loan and, as a result, the carrying value of the loan less the calculated valuation amount does not necessarily represent the fair value of the loan. Real estate collateral is typically valued using independent appraisals or other indications of value based on recent comparable sales of similar properties or assumptions generally observable in the marketplace, adjusted for non-observable inputs. Thus, the resulting nonrecurring fair value measurements are generally classified as Level 3. Estimates of fair value used for other collateral supporting commercial loans generally are based on assumptions not observable in the marketplace and, therefore, such valuations classify as Level 3. Originated mortgage servicing rights are recorded at their fair value at the time of sale of the underlying loan, and are amortized in proportion to and over the estimated period of net servicing income. The fair value of mortgage servicing rights is based on a valuation model incorporating inputs that market participants would use in estimating future net servicing income. Such inputs include estimates of the cost of servicing loans, appropriate discount rate and prepayment speeds and are considered to be unobservable and contribute to the Level 3 classification of mortgage servicing rights. In accordance with GAAP, the Company must record impairment charges, on a nonrecurring basis, when the carrying value of a stratum exceeds its estimated fair value. Impairment is recognized through a valuation allowance. There is a valuation allowance at September 30, 2019 of approximately $ million. There is valuation allowance at December 31, 2018. Other real estate owned (“OREO”) is valued at the time the loan is foreclosed upon and the asset is transferred to OREO. The value is based primarily on third party appraisals, less costs to sell. The appraisals are sometimes further discounted based on management’s historical knowledge, changes in market conditions from the time of valuation, and/or management’s expertise and knowledge of the customer and customer’s business. Such discounts are significant, ranging from 0.5% to 77.4% at September 30, 2019 and result in a Level 3 classification of the inputs for determining fair value. OREO is reviewed and evaluated on at least a quarterly basis for additional impairment and adjusted accordingly, based on the same factors identified above. The Company recovers the carrying value of OREO through the sale of the property. The ability to affect future sales prices is subject to market conditions and factors beyond the Company’s control and may impact the estimated fair value of a property. The Company determines fair values based on quoted market values, where available, estimates of present values, or other valuation techniques. Those techniques are significantly affected by the assumptions used, including, but not limited to, the discount rate and estimates of future cash flows. In that regard, the derived fair value estimates cannot be substantiated by comparison to independent markets and, in many cases, may not be realized in immediate settlement of the instrument. The significant unobservable inputs used in the determination of fair value of assets classified as Level 3 on a recurring or non-recurring basis are as follows: (000's omitted) Fair Value at September 30, 2019 Valuation Technique Significant Unobservable Inputs Significant Unobservable Input Range (Weighted Average) Impaired loans $ 1,729 Fair value of collateral Estimated cost of disposal/market adjustment 9.0% - 40.4% (40.4 %) Other real estate owned 1,258 Fair value of collateral Estimated cost of disposal/market adjustment 0.5% - 77.4% (35.7 %) Mortgage servicing rights 93 Discounted cash flow Weighted average constant prepayment rate 43.0 % Weighted average discount rate 2.69 % Adequate compensation $7/loan (000's omitted) Fair Value at December 31, 2018 Valuation Technique Significant Unobservable Inputs Significant Unobservable Input Range (Weighted Average) Impaired loans $ 1,102 Fair value of collateral Estimated cost of disposal/market adjustment 9.0% - 35.4% (28.8 %) Other real estate owned 1,320 Fair value of collateral Estimated cost of disposal/market adjustment 9.0% - 69.3% (23.8 %) Certain financial instruments and all nonfinancial instruments are excluded from fair value disclosure requirements. Accordingly, the aggregate fair value amounts presented do not represent the underlying value of the Company. The carrying amounts and estimated fair values of the Company’s other financial instruments that are not accounted for at fair value at September 30, 2019 and December 31, 2018 are as follows: September 30, 2019 December 31, 2018 (000's omitted) Carrying Value Fair Value Carrying Value Fair Value Financial assets: Net loans $ 6,803,768 $ 6,971,242 $ 6,231,837 $ 6,247,939 Financial liabilities: Deposits 9,168,285 9,166,701 8,322,371 8,308,765 Short-term borrowings 0 0 54,400 54,400 Securities sold under agreement to repurchase, short-term 233,333 233,333 259,367 259,367 Other long-term debt 4,328 4,303 1,976 1,921 Subordinated notes payable 13,814 13,814 0 0 Subordinated debt held by unconsolidated subsidiary trusts 77,320 77,320 97,939 97,939 The following is a further description of the principal valuation methods used by the Company to estimate the fair values of its financial instruments. Loans have been classified as a Level 3 valuation. Fair values for variable rate loans that reprice frequently are based on carrying values. Fair values for fixed rate loans are estimated using discounted cash flows and interest rates currently being offered for loans with similar terms to borrowers of similar credit quality. Deposits have been classified as a Level 2 valuation. The fair value of demand deposits, interest-bearing checking deposits, savings accounts, and money market deposits is the amount payable on demand at the reporting date. The fair value of time deposit obligations are based on current market rates for similar products. Borrowings, subordinated notes payable subordinated notes payable subordinated notes payable Other financial assets and liabilities – Cash and cash equivalents have been classified as a Level 1 valuation, while accrued interest receivable and accrued interest payable have been classified as a Level 2 valuation. The fair values of each approximate the respective carrying values because the instruments are payable on demand or have short-term maturities and present relatively low credit risk and interest rate risk.

DERIVATIVE INSTRUMENTS

DERIVATIVE INSTRUMENTS	9 Months Ended
	Sep. 30, 2019
DERIVATIVE INSTRUMENTS [Abstract]
DERIVATIVE INSTRUMENTS	NOTE M: DERIVATIVE INSTRUMENTS The Company is party to derivative financial instruments in the normal course of its business to meet the financing needs of its customers and to manage its own exposure to fluctuations in interest rates. These financial instruments have been limited to interest rate swap agreements, commitments to originate real estate loans held for sale and forward sales commitments. The Company does not hold or issue derivative financial instruments for trading or other speculative purposes. The Company enters into forward sales commitments for the future delivery of residential mortgage loans, and interest rate lock commitments to fund loans at a specified interest rate. The forward sales commitments are utilized to reduce interest rate risk associated with interest rate lock commitments and loans held for sale. Changes in the estimated fair value of the forward sales commitments and interest rate lock commitments subsequent to inception are based on changes in the fair value of the underlying loan resulting from the fulfillment of the commitment and changes in the probability that the loan will fund within the terms of the commitment, which is affected primarily by changes in interest rates and the passage of time. At inception and during the life of the interest rate lock commitment, the Company includes the expected net future cash flows related to the associated servicing of the loan as part of the fair value measurement of the interest rate lock commitments. These derivatives are recorded at fair value, which were immaterial at September 30, 2019 and December 31, 2018. The effect of the changes to these derivatives for the three and nine months then ended was also immaterial. The Company acquired interest rate swaps in 2017 with notional amounts with certain commercial customers which totaled $16.8 million at September 30, 2019 and $37.0 million at December 31, 2018. In order to minimize the Company’s risk, these customer derivatives (pay floating/receive fixed swaps) have been offset with essentially matching interest rate swaps (pay fixed/receive floating swaps) with the Company’s counterparty totaling $16.8 million at September 30, 2019 and $37.0 million at December 31, 2018. At September 30, 2019, the weighted average receive rate of these interest rate swaps was 4.01%, the weighted average pay rate was 4.38% and the weighted average maturity was 6.4 years. At December 31, 2018, the weighted average receive rate of these interest rate swaps was 4.34%, the weighted average pay rate was 3.84% and the weighted average maturity was 5.5 years. Hedge accounting has not been applied for these derivatives. Since the terms of the swaps with the customer and the other financial institution offset each other, with the only difference being counterparty credit risk, changes in the fair value of the underlying derivative contracts are not materially different and do not significantly impact our results of operations. The Company also acquired interest rate swaps in 2017 with notional amounts totaling $6.2 million at September 30, 2019, and $6.6 million at December 31, 2018, that were designated as fair value hedges of certain fixed rate loans with municipalities which are recorded in loans in the consolidated statements of condition. At September 30, 2019, the weighted average receive rate of these interest rate swaps was 2.65%, the weighted average pay rate was 3.11% and the weighted average maturity was 13.8 years. At December 31, 2018, the weighted average receive rate of these interest rate swaps was 2.92%, the weighted average pay rate was 3.11% and the weighted average maturity was 14.5 years. The Company includes the gain or loss on the hedged items in interest and fees on loans, the same line item as the offsetting gain or loss on the related interest rate swaps. The effects of fair value accounting in the consolidated statements of income for the three and nine months ended September 30, 2019 are immaterial. As of September 30, 2019, the following amounts were recorded in the consolidated statement of condition related to cumulative basis adjustments for fair value hedges: (000’s omitted) Carrying Amount of the Hedged Assets Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of the Hedged Assets Line Item in the Consolidated Statement of Condition in Which the Hedged Item Is Included September 30, 2019 September 30, 2019 Loans $ 6,307 $ (347 ) Fair values of derivative instruments as of September 30, 2019 are as follows: (000’s omitted) September 30, 2019 Derivative Assets Derivative Liabilities Consolidated Statement of Condition Location Fair Value Consolidated Statement of Condition Location Fair Value Derivatives designated as hedging instruments under Subtopic 815-20 Interest rate swaps Other assets $ 347 Derivatives not designated as hedging instruments under Subtopic 815-20 Interest rate swaps Other assets 748 Accrued interest and other liabilities $ 748 Total derivatives $ 1,095 $ 748 The Company assessed its counterparty risk at September 30, 2019 and determined any credit risk inherent in our derivative contracts was not material. Information about the fair value of derivative financial instruments can be found in Note L to these consolidated financial statements.

SEGMENT INFORMATION

SEGMENT INFORMATION	9 Months Ended
	Sep. 30, 2019
SEGMENT INFORMATION [Abstract]
SEGMENT INFORMATION	NOTE N: SEGMENT INFORMATION Operating segments are components of an enterprise, which are evaluated regularly by the “chief operating decision maker” in deciding how to allocate resources and assess performance. The Company’s chief operating decision maker is the President and Chief Executive Officer of the Company. The Company has identified Banking, Employee Benefit Services and All Other as its reportable operating business segments. Community Bank, N.A. (the “Bank” or “CBNA”) operates the Banking segment that provides full-service banking to consumers, businesses, and governmental units in Upstate New York as well as Northeastern Pennsylvania, Vermont and Western Massachusetts. Employee Benefit Services, which includes the operating subsidiaries Benefit Plans Administrative Services, LLC, BPAS Actuarial and Pension Services, LLC, BPAS Trust Company of Puerto Rico, Northeast Retirement Services, LLC (“NRS”), Global Trust Company, Inc. (“GTC”), and Hand Benefits & Trust Company, provides employee benefit trust, collective investment fund, retirement plan administration, fund administration, transfer agency, actuarial, VEBA/HRA, and health and welfare consulting services. The All Other segment is comprised of: (a) wealth management services including trust services provided by the personal trust unit within the Bank, broker-dealer and investment advisory services provided by CISI and The Carta Group, Inc., as well as asset management provided by Nottingham Advisors, Inc., and (b) full-service insurance, risk management and employee benefit services provided by OneGroup. The accounting policies used in the disclosure of business segments are the same as those described in the summary of significant accounting policies (See Note A, Summary of Significant Accounting Policies Information about reportable segments and reconciliation of the information to the consolidated financial statements follows: (000's omitted) Banking Employee Benefit Services All Other Eliminations Consolidated Total Three Months Ended September 30, 2019 Net interest income $ 91,018 $ 209 $ 49 $ 0 $ 91,276 Provision for loan losses 1,751 0 0 0 1,751 Noninterest revenues 17,790 24,830 15,143 (669 ) 57,094 Amortization of intangible assets 1,439 1,667 854 0 3,960 Acquisition expenses 6,061 0 0 0 6,061 Other operating expenses 61,839 14,721 11,017 (669 ) 86,908 Income before income taxes $ 37,718 $ 8,651 $ 3,321 $ 0 $ 49,690 Assets $ 11,398,191 $ 201,442 $ 74,169 $ (76,505 ) $ 11,597,297 Goodwill $ 670,023 $ 83,275 $ 20,312 $ 0 $ 773,610 Core deposit intangibles & Other intangibles $ 17,872 $ 39,440 $ 9,763 $ 0 $ 67,075 Three Months Ended September 30, 2018 Net interest income $ 86,060 $ 102 $ 36 $ 0 $ 86,198 Provision for loan losses 2,215 0 0 0 2,215 Noninterest revenues 18,002 23,815 14,737 (763 ) 55,791 Amortization of intangible assets 1,535 1,970 922 0 4,427 Acquisition expenses (832 ) 0 0 0 (832 ) Other operating expenses 57,863 14,025 10,513 (763 ) 81,638 Income before income taxes $ 43,281 $ 7,922 $ 3,338 $ 0 $ 54,541 Assets $ 10,440,732 $ 205,565 $ 66,470 $ (53,200 ) $ 10,659,567 Goodwill $ 629,916 $ 83,275 $ 20,288 $ 0 $ 733,479 Core deposit intangibles & Other intangibles $ 20,111 $ 46,514 $ 11,596 $ 0 $ 78,221 (000's omitted) Banking Employee Benefit Services All Other Eliminations Consolidated Total Nine Months Ended September 30, 2019 Net interest income $ 265,860 $ 448 $ 127 $ 0 $ 266,435 Provision for loan losses 5,573 0 0 0 5,573 Noninterest revenues 57,059 73,919 44,749 (2,231 ) 173,496 Amortization of intangible assets 4,297 5,105 2,592 0 11,994 Acquisition expenses 7,789 0 0 0 7,789 Other operating expenses 182,186 43,985 33,034 (2,231 ) 256,974 Income before income taxes $ 123,074 $ 25,277 $ 9,250 $ 0 $ 157,601 Nine Months Ended September 30, 2018 Net interest income $ 257,313 $ 264 $ 91 $ 0 $ 257,668 Provision for loan losses 8,342 0 0 0 8,342 Noninterest revenues 58,399 70,316 43,285 (2,159 ) 169,841 Amortization of intangible assets 4,914 6,047 2,819 0 13,780 Acquisition expenses (782 ) 7 6 0 (769 ) Other operating expenses 172,283 41,938 32,603 (2,159 ) 244,665 Income before income taxes $ 130,955 $ 22,588 $ 7,948 $ 0 $ 161,491

BASIS OF PRESENTATION (Policies

BASIS OF PRESENTATION (Policies)	9 Months Ended
	Sep. 30, 2019
BASIS OF PRESENTATION [Abstract]
Basis of Presentation	The interim financial data as of and for the three and nine months ended September 30, 2019 is unaudited; however, in the opinion of Community Bank System, Inc. (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 conformity with generally accepted accounting principles in the United States of America (“GAAP”). 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.

ACCOUNTING POLICIES (Policies)

ACCOUNTING POLICIES (Policies)	9 Months Ended
	Sep. 30, 2019
ACCOUNTING POLICIES [Abstract]
Leases	Leases The Company occupies certain offices and uses certain equipment under non-cancelable operating lease agreements. The Company determines if an arrangement is a lease at inception. The right-of-use assets associated with operating leases are recorded in premises and equipment in the Company’s consolidated statements of condition. The lease liabilities associated with operating leases are included in accrued interest and other liabilities in the Company’s consolidated statements of condition. Right-of-use assets represent the Company’s right to use the underlying assets for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the associated leases. Operating lease right-of-use assets and liabilities are recognized at the commencement date of the lease based on the present value of lease payments over the lease term. The Company uses interest rates on advances from the Federal Home Loan Bank of New York available at the time of commencement to determine the present value of lease payments. The operating lease right-of-use assets include any lease payments made at the time of commencement and exclude lease incentives. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the option will be exercised. Lease expense is recognized on a straight-line basis over the lease term and is included in occupancy and equipment expense in the Company’s consolidated statements of income. The Company elected to account for lease and non-lease components separately, applies a portfolio approach to account for the lease right-of-use assets and liabilities for certain equipment leases and elected to exclude leases with a term of 12 months or less from the recognition and measurement policies described above.
Derivative Financial Instruments and Hedging Activities	Derivative Financial Instruments and Hedging Activities The Company accounts for derivative financial instruments at fair value. If certain conditions are met, a derivative may be specifically designated as (1) a hedge of the exposure to changes in the fair value of a recognized asset or liability or an unrecognized firm commitment (“fair value hedge”), (2) a hedge of the exposure to variable cash flows of a forecasted transaction or the variability of cash flows to be received or paid related to a recognized asset or liability (“cash flow hedge”), or (3) an instrument with no hedging designation (“stand-alone derivative”). For a fair value hedge, the gain or loss on the derivative, as well as the offsetting loss or gain on the hedged item, are recognized in current earnings as fair values change. For a cash flow hedge, the gain or loss on the derivative is reported in other comprehensive income and is reclassified into earnings in the same periods during which the hedged transaction affects earnings. Changes in the fair value of derivatives that do not qualify for hedge accounting are reported currently in earnings, as noninterest revenues. Net cash settlements on derivatives that qualify for hedge accounting are recorded in interest income or interest expense, based on the item being hedged. Net cash settlements on derivatives that do not qualify for hedge accounting are reported in noninterest revenues. Cash flows on hedges are classified in the consolidated statements of cash flow statement the same as the cash flows of the items being hedged. The Company formally documents the relationship between derivatives and hedged items, as well as the risk-management objective and strategy for undertaking hedge transactions at the inception of the hedging relationship. This documentation includes linking the fair value or cash flow hedges to specific assets and liabilities on the statements of condition or to specific commitments or forecasted transactions. When hedge accounting is discontinued, subsequent changes in fair value of the derivative are recorded in noninterest revenues. When a fair value hedge is discontinued, the hedged asset or liability is no longer adjusted for changes in fair value and the existing basis adjustment is amortized or accreted over the remaining life of the asset or liability. When a cash flow hedge is discontinued, but the hedged cash flows or forecasted transactions are still expected to occur, gains or losses that were accumulated in other comprehensive income are amortized into earnings over the same periods which the hedged transactions will affect earnings.
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) Topic 840, Leases In August 2017, the FASB issued ASU No. 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities.
New Accounting Pronouncements	New Accounting Pronouncements In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments – Credit Losses (Topic 326) The Company is currently evaluating the impact CECL will have on the Company’s consolidated financial statements, and expects a change in the allowance for loan losses resulting from the change to expected losses for the estimated life of the financial asset. Management has developed its CECL model for the Company’s loan portfolio, which utilizes its historical data through September 30, 2019, as well as current and expected economic conditions and forecasts. The Company has completed the evaluation of its data requirements, determined its loan segments, determined the model construct for each segment, developed its qualitative framework and produced an estimated Allowance for Credit Loss amount based on the September 30, 2019 data inputs, assumptions and mathematical calculations. The Company is in the process of evaluating the model’s sensitivity to various model inputs, as well as identifying the key controls around model development, quarterly model operations and the production of quarterly and annual financial statement disclosures. Based on the preliminary September model results, the Company believes it will establish an Allowance for Credit Losses at the time of adoption of between and . This compares to an allowance for loan losses of at September based on the current incurred loss model and represents approximately a to increase in the Company’s allowance. These results should be considered preliminary and may change due to factors including, but not limited to, changes in estimated historical losses, changes in the Company’s asset quality trends, changes in current economic conditions and changes in the Company’s economic forecast. Upon adoption, the Company does not expect to record any material allowance for credit losses on its available-for-sale debt securities or on its other instruments carried at amortized cost, other than its held-for-investment loan portfolio. The Company’s regulators will permit financial institutions to “phase-in” the impact of CECL on its regulatory capital ratios over years with transitional relief of incremental capital requirements. The Company does not expect to utilize the phased-in approach and instead anticipates it will record the entire cumulative-effect adjustment against its regulatory capital at the time of adoption. In January 2017, the FASB issued ASU No. 2017-04, Intangibles-Goodwill and Other (Topic 350)

ACQUISITIONS (Tables)

ACQUISITIONS (Tables)	9 Months Ended
	Sep. 30, 2019
ACQUISITIONS [Abstract]
Estimated Fair Value of Assets Acquired and Liabilities Assumed	The following table summarizes the estimated fair value of the assets acquired and liabilities assumed after considering the measurement period adjustments described above: 2019 2018 (000s omitted) Kinderhook Other (1) Total Other (2) Consideration paid : Cash $ 93,384 $ 1,650 $ 95,034 $ 1,753 Total net consideration paid $ 93,384 $ 1,650 $ 95,034 $ 1,753 Recognized amounts of identifiable assets acquired and liabilities assumed: Cash and cash equivalents 90,381 0 90,381 16 Available-for-sale investment securities 37,653 0 37,653 0 Equity and other securities 2,117 0 2,117 0 Loans 479,931 0 479,931 0 Premises and equipment 13,970 0 13,970 10 Accrued interest and fees receivable 1,119 0 1,119 0 Other assets 14,144 0 14,144 105 Core deposit intangibles 3,573 0 3,573 0 Other intangibles 0 1,650 1,650 1,343 Deposits (568,081 ) 0 (568,081 ) 0 Other liabilities (3,217 ) 0 (3,217 ) (31 ) Subordinated notes payable (13,831 ) 0 (13,831 ) 0 Other long-term debt (2,420 ) 0 (2,420 ) 0 Subordinated debt held by unconsolidated subsidiary trusts (2,062 ) 0 (2,062 ) 0 Total identifiable assets, net 53,277 1,650 54,927 1,443 Goodwill $ 40,107 $ 0 $ 40,107 $ 310 (1) completed by CISI in 2019. (2)
Loans Acquired	The following is a summary of the loans acquired from Kinderhook at the date of acquisition: (000s omitted) Acquired Impaired Loans Acquired Non-impaired Loans Total Acquired Loans Contractually required principal and interest at acquisition $ 12,661 $ 591,694 $ 604,355 Contractual cash flows not expected to be collected (4,096 ) (5,472 ) (9,568 ) Expected cash flows at acquisition 8,565 586,222 594,787 Interest component of expected cash flows (512 ) (114,344 ) (114,856 ) Fair value of acquired loans $ 8,053 $ 471,878 $ 479,931
Pro Forma Financial Information	The pro forma information set forth below reflects the historical results of Kinderhook combined with the Company’s consolidated statement of income with adjustments related to (a) certain purchase accounting fair value adjustments and (b) amortization of customer lists and core deposit intangibles. Acquisition-related expenses totaling $6.1 million and $7.8 million for the three and nine months ended September 30, 2019 were included in the pro forma information as if they were incurred in the first quarter of 2018. Pro Forma (Unaudited) Three Months Ended Pro Forma (Unaudited) Nine Months Ended (000’s omitted) September 30, 2019 September 30, 2018 September 30, 2019 September 30, 2018 Total revenue, net of interest expense $ 149,087 $ 148,152 $ 452,995 $ 446,084 Net income 44,154 44,313 135,370 125,505

INVESTMENT SECURITIES (Tables)

INVESTMENT SECURITIES (Tables)	9 Months Ended
	Sep. 30, 2019
INVESTMENT SECURITIES [Abstract]
Amortized Cost and Estimated Fair Value of Investment Securities	The amortized cost and estimated fair value of investment securities as of September 30, 2019 and December 31, 2018 are as follows: September 30, 2019 December 31, 2018 (000's omitted) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Available-for-Sale Portfolio: U.S. Treasury and agency securities $ 1,482,739 $ 24,122 $ 214 $ 1,506,647 $ 2,036,474 $ 2,190 $ 14,911 $ 2,023,753 Obligations of state and political subdivisions 442,942 15,159 11 458,090 453,640 6,563 1,049 459,154 Government agency mortgage-backed securities 406,329 6,330 843 411,816 390,234 1,526 9,283 382,477 Corporate debt securities 2,542 0 2 2,540 2,588 0 42 2,546 Government agency collateralized mortgage obligations 57,452 592 35 58,009 69,342 60 1,283 68,119 Total available-for-sale portfolio $ 2,392,004 $ 46,203 $ 1,105 $ 2,437,102 $ 2,952,278 $ 10,339 $ 26,568 $ 2,936,049 Equity and other Securities: Equity securities, at fair value $ 251 $ 210 $ 0 $ 461 $ 251 $ 200 $ 19 $ 432 Federal Home Loan Bank common stock 6,912 0 0 6,912 8,768 0 0 8,768 Federal Reserve Bank common stock 31,992 0 0 31,992 30,690 0 0 30,690 Other equity securities, at adjusted cost 4,525 750 0 5,275 4,969 750 0 5,719 Total equity and other securities $ 43,680 $ 960 $ 0 $ 44,640 $ 44,678 $ 950 $ 19 $ 45,609
Summary of Investment Securities That Have Been in a Continuous Unrealized Loss Position for Less Than or Greater Than Twelve Months	As of September 30, 2019 Less than 12 Months 12 Months or Longer Total (000's omitted) # Fair Value Gross Unrealized Losses # Fair Value Gross Unrealized Losses # Fair Value Gross Unrealized Losses Available-for-Sale Portfolio: U.S. Treasury and agency securities 6 $ 77,332 $ 58 12 $ 107,840 $ 156 18 $ 185,172 $ 214 Obligations of state and political subdivisions 73 7,125 11 0 0 0 73 7,125 11 Government agency mortgage-backed securities 24 34,660 95 55 58,473 748 79 93,133 843 Corporate debt securities 0 0 0 1 2,540 2 1 2,540 2 Government agency collateralized mortgage obligations 5 6,662 9 7 5,357 26 12 12,019 35 Total available-for-sale investment portfolio 108 $ 125,779 $ 173 75 $ 174,210 $ 932 183 $ 299,989 $ 1,105 As of December 31, 2018 Less than 12 Months 12 Months or Longer Total (000's omitted) # Fair Value Gross Unrealized Losses # Fair Value Gross Unrealized Losses # Fair Value Gross Unrealized Losses Available-for-Sale Portfolio: U.S. Treasury and agency securities 7 $ 473,082 $ 682 64 $ 1,213,276 $ 14,229 71 $ 1,686,358 $ 14,911 Obligations of state and political subdivisions 118 55,671 216 97 51,753 833 215 107,424 1,049 Government agency mortgage-backed securities 43 47,708 258 181 253,931 9,025 224 301,639 9,283 Corporate debt securities 0 0 0 1 2,546 42 1 2,546 42 Government agency collateralized mortgage obligations 1 66 0 41 63,112 1,283 42 63,178 1,283 Total available-for-sale investment portfolio 169 $ 576,527 $ 1,156 384 $ 1,584,618 $ 25,412 553 $ 2,161,145 $ 26,568 Equity and other Securities: Equity securities, at fair value 1 $ 82 $ 19 0 $ 0 $ 0 1 $ 82 $ 19 Total equity and other securities 1 $ 82 $ 19 0 $ 0 $ 0 1 $ 82 $ 19
Amortized Cost and Estimated Fair Value of Debt Securities by Contractual Maturity	The amortized cost and estimated fair value of debt securities at September 30, 2019, by contractual maturity, are shown below. Expected maturities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. Securities not due at a single maturity date are shown separately. Available-for-Sale (000's omitted) Amortized Cost Fair Value Due in one year or less $ 71,512 $ 71,510 Due after one through five years 1,512,018 1,538,064 Due after five years through ten years 54,176 58,251 Due after ten years 290,517 299,452 Subtotal 1,928,223 1,967,277 Government agency mortgage-backed securities 406,329 411,816 Government agency collateralized mortgage obligations 57,452 58,009 Total $ 2,392,004 $ 2,437,102

LOANS (Tables)

LOANS (Tables)	9 Months Ended
	Sep. 30, 2019
Loans and Leases Receivable Disclosure [Line Items]
Loans Receivable, Net	The balances of these classes are summarized as follows: (000's omitted) September 30, 2019 December 31, 2018 Business lending $ 2,779,612 $ 2,396,977 Consumer mortgage 2,405,191 2,235,408 Consumer indirect 1,091,980 1,083,207 Consumer direct 187,379 178,820 Home equity 389,029 386,709 Gross loans, including deferred origination costs 6,853,191 6,281,121 Allowance for loan losses (49,423 ) (49,284 ) Loans, net of allowance for loan losses $ 6,803,768 $ 6,231,837
Accretable Discount Related to Credit Impaired Acquired Loans	The outstanding balance related to credit impaired acquired loans was $16.7 million and $7.4 million at September 30, 2019 and December 31, 2018, respectively. The changes in the accretable discount related to the credit impaired acquired loans are as follows: (000’s omitted) Balance at December 31, 2018 $ 437 Accretion recognized, year-to-date (302 ) Net reclassification from non-accretable to accretable 96 Kinderhook acquisition 512 Balance at September 30, 2019 $ 743
Aged Analysis of Past Due Loans by Class	Legacy Loans (excludes loans acquired after January 1, 2009) (000’s omitted) Past Due 30 – 89 Days 90+ Days Past Due and Still Accruing Nonaccrual Total Past Due Current Total Loans Business lending $ 2,697 $ 189 $ 4,590 $ 7,476 $ 1,778,596 $ 1,786,072 Consumer mortgage 11,038 2,976 10,650 24,664 1,921,265 1,945,929 Consumer indirect 10,307 177 0 10,484 1,074,849 1,085,333 Consumer direct 1,046 38 0 1,084 177,242 178,326 Home equity 1,496 354 1,404 3,254 308,375 311,629 Total $ 26,584 $ 3,734 $ 16,644 $ 46,962 $ 5,260,327 $ 5,307,289 Acquired Loans (000’s omitted) Past Due 30 – 89 Days 90+ Days Past Due and Still Accruing Nonaccrual Total Past Due Acquired Impaired (1) Current Total Loans Business lending $ 747 $ 997 $ 3,957 $ 5,701 $ 11,508 $ 976,331 $ 993,540 Consumer mortgage 1,573 171 2,409 4,153 0 455,109 459,262 Consumer indirect 33 32 0 65 0 6,582 6,647 Consumer direct 86 5 54 145 0 8,908 9,053 Home equity 279 125 546 950 0 76,450 77,400 Total $ 2,718 $ 1,330 $ 6,966 $ 11,014 $ 11,508 $ 1,523,380 $ 1,545,902 (1) Acquired impaired loans were not classified as nonperforming assets as the loans are considered to be performing under ASC 310-30. As a result interest income, through the accretion of the difference between the carrying amount of the loans and the expected cashflows, is being recognized on all acquired impaired loans. The following is an aged analysis of the Company’s past due loans by class as of December 31, 2018: Legacy Loans (000’s omitted) Past Due 30 – 89 Days 90+ Days Past Due and Still Accruing Nonaccrual Total Past Due Current Total Loans Business lending $ 5,261 $ 179 $ 4,872 $ 10,312 $ 1,608,515 $ 1,618,827 Consumer mortgage 12,468 1,393 9,872 23,733 1,824,717 1,848,450 Consumer indirect 14,609 258 0 14,867 1,057,525 1,072,392 Consumer direct 1,778 48 0 1,826 173,948 175,774 Home equity 983 228 1,438 2,649 309,892 312,541 Total $ 35,099 $ 2,106 $ 16,182 $ 53,387 $ 4,974,597 $ 5,027,984 Acquired Loans (000’s omitted) Past Due 30 – 89 Days 90+ Days Past Due and Still Accruing Nonaccrual Total Past Due Acquired Impaired (1) Current Total Loans Business lending $ 974 $ 0 $ 3,498 $ 4,472 $ 5,446 $ 768,232 $ 778,150 Consumer mortgage 841 232 2,390 3,463 0 383,495 386,958 Consumer indirect 78 34 0 112 0 10,703 10,815 Consumer direct 115 4 0 119 0 2,927 3,046 Home equity 613 79 474 1,166 0 73,002 74,168 Total $ 2,621 $ 349 $ 6,362 $ 9,332 $ 5,446 $ 1,238,359 $ 1,253,137 (1) Acquired impaired loans were not classified as nonperforming assets as the loans are considered to be performing under ASC 310-30. As a result interest income, through the accretion of the difference between the carrying amount of the loans and the expected cashflows, is being recognized on all acquired impaired loans.
Non-Business Impaired Loans	All loan classes are collectively evaluated for impairment except business lending. A summary of individually evaluated impaired loans as of September 30, 2019 and December 31, 2018 follows: (000’s omitted) September 30, 2019 December 31, 2018 Loans with allowance allocation $ 0 $ 3,956 Loans without allowance allocation 5,172 2,230 Carrying balance 5,172 6,186 Contractual balance 11,896 12,078 Specifically allocated allowance 0 956
Troubled Debt Restructurings on Financing Receivables	Information regarding TDRs as of September 30, 2019 and December 31, 2018 is as follows: September 30, 2019 December 31, 2018 (000’s omitted) Nonaccrual Accruing Total Nonaccrual Accruing Total # Amount # Amount # Amount # Amount # Amount # Amount Business lending 5 $ 662 3 $ 205 8 $ 867 4 $ 162 2 $ 165 6 $ 327 Consumer mortgage 57 2,527 49 1,945 106 4,472 46 1,986 46 1,769 92 3,755 Consumer indirect 0 0 77 854 77 854 0 0 77 857 77 857 Consumer direct 0 0 22 91 22 91 0 0 22 71 22 71 Home equity 13 230 11 310 24 540 12 240 9 275 21 515 Total 75 $ 3,419 162 $ 3,405 237 $ 6,824 62 $ 2,388 156 $ 3,137 218 $ 5,525 The following table presents information related to loans modified in a TDR during the three months and nine months ended September 30, 2019 and 2018. Of the loans noted in the table below, all consumer mortgage loans for the three months and nine months ended September 30, 2019 and 2018 were modified due to a Chapter 7 bankruptcy as described previously. The financial effects of these restructurings were immaterial. Three Months Ended September 30, 2019 Three Months Ended September 30, 2018 (000’s omitted) Number of loans modified Outstanding Balance Number of loans modified Outstanding Balance Business lending 1 $ 415 0 $ 0 Consumer mortgage 8 464 4 195 Consumer indirect 10 116 14 117 Consumer direct 2 25 2 10 Home equity 0 0 1 0 Total 21 $ 1,020 21 $ 322 Nine Months Ended September 30, 2019 Nine Months Ended September 30, 2018 (000’s omitted) Number of loans modified Outstanding Balance Number of loans modified Outstanding Balance Business lending 3 $ 660 1 $ 93 Consumer mortgage 19 1,271 7 407 Consumer indirect 22 206 24 176 Consumer direct 5 35 5 21 Home equity 4 72 2 85 Total 53 $ 2,244 39 $ 782
Allowance for Loan Losses by Class	The allowance for loan losses is general in nature and is available to absorb losses from any loan type despite the analysis below. The following presents by class the activity in the allowance for loan losses: Three Months Ended September 30, 2019 (000’s omitted) Business Lending Consumer Mortgage Consumer Indirect Consumer Direct Home Equity Unallocated Acquired Impaired Total Beginning balance $ 17,769 $ 10,763 $ 14,345 $ 3,184 $ 2,103 $ 991 $ 155 $ 49,310 Charge-offs (305 ) (200 ) (2,224 ) (456 ) (45 ) 0 0 (3,230 ) Recoveries 290 8 1,095 167 32 0 0 1,592 Provision 301 (94 ) 1,221 383 (8 ) (53 ) 1 1,751 Ending balance $ 18,055 $ 10,477 $ 14,437 $ 3,278 $ 2,082 $ 938 $ 156 $ 49,423 Three Months Ended September 30, 2018 (000’s omitted) Business Lending Consumer Mortgage Consumer Indirect Consumer Direct Home Equity Unallocated Acquired Impaired Total Beginning balance $ 18,439 $ 10,473 $ 14,424 $ 3,164 $ 2,015 $ 1,070 $ 33 $ 49,618 Charge-offs (73 ) (144 ) (2,364 ) (465 ) (221 ) 0 0 (3,267 ) Recoveries 93 46 1,190 223 15 0 0 1,567 Provision 321 (205 ) 1,719 299 225 (159 ) 15 2,215 Ending balance $ 18,780 $ 10,170 $ 14,969 $ 3,221 $ 2,034 $ 911 $ 48 $ 50,133 Nine Months Ended September 30, 2019 (000’s omitted) Business Lending Consumer Mortgage Consumer Indirect Consumer Direct Home Equity Unallocated Acquired Impaired Total Beginning balance $ 18,522 $ 10,124 $ 14,366 $ 3,095 $ 2,144 $ 1,000 $ 33 $ 49,284 Charge-offs (1,774 ) (1,040 ) (5,529 ) (1,436 ) (223 ) 0 0 (10,002 ) Recoveries 593 44 3,296 567 68 0 0 4,568 Provision 714 1,349 2,304 1,052 93 (62 ) 123 5,573 Ending balance $ 18,055 $ 10,477 $ 14,437 $ 3,278 $ 2,082 $ 938 $ 156 $ 49,423 Nine Months Ended September 30, 2018 (000’s omitted) Business Lending Consumer Mortgage Consumer Indirect Consumer Direct Home Equity Unallocated Acquired Impaired Total Beginning balance $ 17,257 $ 10,465 $ 13,468 $ 3,039 $ 2,107 $ 1,100 $ 147 $ 47,583 Charge-offs (2,000 ) (588 ) (6,031 ) (1,324 ) (325 ) 0 (368 ) (10,636 ) Recoveries 404 109 3,688 612 31 0 0 4,844 Provision 3,119 184 3,844 894 221 (189 ) 269 8,342 Ending balance $ 18,780 $ 10,170 $ 14,969 $ 3,221 $ 2,034 $ 911 $ 48 $ 50,133
Business Lending [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans by Credit Quality Indicator	The following table shows the amount of business lending loans by credit quality category: September 30, 2019 December 31, 2018 (000’s omitted) Legacy Acquired Total Legacy Acquired Total Pass $ 1,609,382 $ 886,363 $ 2,495,745 $ 1,439,337 $ 702,493 $ 2,141,830 Special mention 91,159 61,289 152,448 105,065 40,107 145,172 Classified 85,531 34,380 119,911 74,425 28,525 102,950 Doubtful 0 0 0 0 1,579 1,579 Acquired impaired 0 11,508 11,508 0 5,446 5,446 Total $ 1,786,072 $ 993,540 $ 2,779,612 $ 1,618,827 $ 778,150 $ 2,396,977
All Other Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans by Credit Quality Indicator	All other loans are underwritten and structured using standardized criteria and characteristics, primarily payment performance, and are normally risk rated and monitored collectively on a monthly basis. These are typically loans to individuals in the consumer categories and are delineated as either performing or nonperforming. Performing loans include loans classified as current as well as those classified as 30 - 89 days past due. Nonperforming loans include 90+ days past due and still accruing and nonaccrual loans. The following table details the balances in all other loan categories at September 30, 2019: Legacy Loans (000’s omitted) Consumer Mortgage Consumer Indirect Consumer Direct Home Equity Total Performing $ 1,932,303 $ 1,085,156 $ 178,288 $ 309,871 $ 3,505,618 Nonperforming 13,626 177 38 1,758 15,599 Total $ 1,945,929 $ 1,085,333 $ 178,326 $ 311,629 $ 3,521,217 Acquired Loans (000’s omitted) Consumer Mortgage Consumer Indirect Consumer Direct Home Equity Total Performing $ 456,682 $ 6,615 $ 8,994 $ 76,729 $ 549,020 Nonperforming 2,580 32 59 671 3,342 Total $ 459,262 $ 6,647 $ 9,053 $ 77,400 $ 552,362 The following table details the balances in all other loan categories at December 31, 2018: Legacy Loans (000’s omitted) Consumer Mortgage Consumer Indirect Consumer Direct Home Equity Total Performing $ 1,837,185 $ 1,072,134 $ 175,726 $ 310,875 $ 3,395,920 Nonperforming 11,265 258 48 1,666 13,237 Total $ 1,848,450 $ 1,072,392 $ 175,774 $ 312,541 $ 3,409,157 Acquired Loans (000’s omitted) Consumer Mortgage Consumer Indirect Consumer Direct Home Equity Total Performing $ 384,336 $ 10,781 $ 3,042 $ 73,615 $ 471,774 Nonperforming 2,622 34 4 553 3,213 Total $ 386,958 $ 10,815 $ 3,046 $ 74,168 $ 474,987

GOODWILL AND IDENTIFIABLE INT_2

GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS (Tables)	9 Months Ended
	Sep. 30, 2019
GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS [Abstract]
Gross Carrying Amount and Accumulated Amortization of Identifiable Intangible Assets	The gross carrying amount and accumulated amortization for each type of identifiable intangible asset are as follows: September 30, 2019 December 31, 2018 (000's omitted) Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Amortizing intangible assets: Core deposit intangibles $ 66,475 $ (48,603 ) $ 17,872 $ 62,902 $ (44,306 ) $ 18,596 Other intangibles 89,266 (40,063 ) 49,203 87,616 (32,366 ) 55,250 Total amortizing intangibles $ 155,741 $ (88,666 ) $ 67,075 $ 150,518 $ (76,672 ) $ 73,846
Estimated Aggregate Amortization Expense for Each of Five Succeeding Fiscal Years	The estimated aggregate amortization expense for each of the five succeeding fiscal years ended December 31 is as follows: (000's omitted) Oct - Dec 2019 $ 3,962 2020 13,801 2021 11,786 2022 10,105 2023 8,457 Thereafter 18,964 Total $ 67,075
Components of Goodwill	Shown below are the components of the Company’s goodwill at December 31, 2018 and September 30, 2019: (000’s omitted) December 31, 2018 Activity September 30, 2019 Goodwill $ 738,327 $ 40,107 $ 778,434 Accumulated impairment (4,824 ) 0 (4,824 ) Goodwill, net $ 733,503 $ 40,107 $ 773,610

LEASES (Tables)

LEASES (Tables)	9 Months Ended
	Sep. 30, 2019
LEASES [Abstract]
Components of Lease Expense	The components of lease expense are as follows: (000’s omitted) Three Months Ended September 30, 2019 Nine Months Ended September 30, 2019 Operating lease cost $ 2,231 $ 6,493 Variable lease cost 9 9 Short-term lease cost (1) 77 180 Total lease cost $ 2,317 $ 6,682 (1) Short-term lease cost includes the cost of leases with terms of twelve months or less, excluding leases with terms of one month or less.
Supplemental Cash Flow Information Related to Leases	Supplemental cash flow information related to leases is as follows: (000’s omitted) Nine Months Ended September 30, 2019 Cash paid for amounts included in the measurement of lease liabilities: Operating cash outflows for operating leases $ 5,987 Right-of-use assets obtained in exchange for lease obligations: Operating leases 13,766
Supplemental Balance Sheet Information Related to Leases	Supplemental balance sheet information related to leases is as follows: (000’s omitted, except lease term and discount rate) September 30, 2019 Operating leases Operating lease right-of-use assets $ 41,948 Operating lease liabilities 42,769 Weighted average remaining lease term Operating leases 6.7 years Weighted average discount rate Operating leases 2.95 %
Operating Leases [Abstract]
Maturities of Lease Liabilities	Maturities of lease liabilities as of September 30, 2019 are as follows: (000’s omitted) Operating Leases Oct - Dec 2019 $ 2,253 2020 9,372 2021 7,934 2022 6,645 2023 5,674 Thereafter 15,697 Total lease payments 47,575 Less imputed interest (4,806 ) Total $ 42,769
706 North Clinton, LLC [Member]
Operating Leases [Abstract]
Maturities of Lease Liabilities	Included in the Company’s operating leases are related party leases where BPAS Actuarial & Pension Services, LLC and OneGroup NY, Inc., subsidiaries of the Company, lease office space from 706 North Clinton, LLC., an entity the Company holds a 50 % membership interest in through its subsidiary Oneida Preferred Funding II, LLC. As of September 30, 2019, the operating lease right-of-use assets and operating lease liabilities associated with these related party leases total $5.0 million and $5.0 million, respectively. As of September 30, 2019, the weighted average remaining lease term and weighted average discount rate for the Company’s related party leases are 10.2 years and 3.67 %, respectively. The maturities of the Company’s related party lease liabilities as of September 30, 2019 are as follows: (000’s omitted) 706 North Clinton, LLC Oct - Dec 2019 $ 148 2020 591 2021 591 2022 591 2023 591 Thereafter 3,538 Total lease payments 6,050 Less imputed interest (1,011 ) Total $ 5,039

MANDATORILY REDEEMABLE PREFER_2

MANDATORILY REDEEMABLE PREFERRED SECURITIES (Tables)	9 Months Ended
	Sep. 30, 2019
MANDATORILY REDEEMABLE PREFERRED SECURITIES [Abstract]
Terms of Preferred Securities	As of September 30, 2019, the terms of the preferred securities of CCT IV are as follows: Issuance Par Maturity Trust Date Amount Interest Rate Date Call Price CCT IV 12/8/2006 $75.0 million 3 month LIBOR plus 1.65% (3.77%) 12/15/2036 Par

BENEFIT PLANS (Tables)

BENEFIT PLANS (Tables)	9 Months Ended
	Sep. 30, 2019
BENEFIT PLANS [Abstract]
Net Periodic Benefit Cost	The net periodic benefit cost for the three and nine months ended September 30, 2019 and 2018 is as follows: Pension Benefits Post-retirement Benefits Three Months Ended Nine Months Ended Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, (000's omitted) 2019 2018 2019 2018 2019 2018 2019 2018 Service cost $ 1,270 $ 1,154 $ 3,811 $ 3,396 $ 0 $ 0 $ 0 $ 0 Interest cost 1,566 1,422 4,698 4,251 18 18 53 52 Expected return on plan assets (3,578 ) (3,705 ) (10,733 ) (11,115 ) 0 0 0 0 Amortization of unrecognized net loss 642 299 1,926 895 9 5 28 15 Amortization of prior service cost 17 (60 ) 48 (225 ) (45 ) (45 ) (134 ) (134 ) Net periodic benefit $ (83 ) $ (890 ) $ (250 ) $ (2,798 ) $ (18 ) $ (22 ) $ (53 ) $ (67 )

EARNINGS PER SHARE (Tables)

EARNINGS PER SHARE (Tables)	9 Months Ended
	Sep. 30, 2019
EARNINGS PER SHARE [Abstract]
Reconciliation of Basic to Diluted Earnings per Share	The following is a reconciliation of basic to diluted earnings per share for the three and nine months ended September 30, 2019 and 2018: Three Months Ended Nine Months Ended September 30, September 30, (000's omitted, except per share data) 2019 2018 2019 2018 Net income $ 39,218 $ 43,106 $ 126,179 $ 127,818 Income attributable to unvested stock-based compensation awards (102 ) (191 ) (331 ) (563 ) Income available to common shareholders $ 39,116 $ 42,915 $ 125,848 $ 127,255 Weighted-average common shares outstanding – basic 51,750 51,250 51,644 51,108 Basic earnings per share $ 0.76 $ 0.84 $ 2.44 $ 2.49 Net income $ 39,218 $ 43,106 $ 126,179 $ 127,818 Income attributable to unvested stock-based compensation awards (102 ) (191 ) (331 ) (563 ) Income available to common shareholders $ 39,116 $ 42,915 $ 125,848 $ 127,255 Weighted-average common shares outstanding – basic 51,750 51,250 51,644 51,108 Assumed exercise of stock options 496 608 522 590 Weighted-average common shares outstanding – diluted 52,246 51,858 52,166 51,698 Diluted earnings per share $ 0.75 $ 0.83 $ 2.41 $ 2.46

COMMITMENTS, CONTINGENT LIABI_2

COMMITMENTS, CONTINGENT LIABILITIES AND RESTRICTIONS (Tables)	9 Months Ended
	Sep. 30, 2019
COMMITMENTS, CONTINGENT LIABILITIES AND RESTRICTIONS [Abstract]
Off Balance Sheet Financial Instruments Contract Amounts	The contract amounts of commitments and contingencies are as follows: (000's omitted) September 30, 2019 December 31, 2018 Commitments to extend credit $ 1,065,127 $ 1,134,576 Standby letters of credit 37,968 33,169 Total $ 1,103,095 $ 1,167,745

FAIR VALUE (Tables)

FAIR VALUE (Tables)	9 Months Ended
	Sep. 30, 2019
FAIR VALUE [Abstract]
Fair Value Measured on a Recurring Basis	A financial instrument’s categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement. The following tables set forth the Company’s financial assets and liabilities that were accounted for at fair value on a recurring basis. There were no transfers between any of the levels for the periods presented. September 30, 2019 (000's omitted) Level 1 Level 2 Level 3 Total Fair Value Available-for-sale investment securities: U.S. Treasury and agency securities $ 1,343,370 $ 163,277 $ 0 $ 1,506,647 Obligations of state and political subdivisions 0 458,090 0 458,090 Government agency mortgage-backed securities 0 411,816 0 411,816 Corporate debt securities 0 2,540 0 2,540 Government agency collateralized mortgage obligations 0 58,009 0 58,009 Total available-for-sale investment securities 1,343,370 1,093,732 0 2,437,102 Equity securities 461 0 0 461 Interest rate swap agreements asset 0 1,095 0 1,095 Interest rate swap agreements liability 0 (748 ) 0 (748 ) Total $ 1,343,831 $ 1,094,079 $ 0 $ 2,437,910 December 31, 2018 (000's omitted) Level 1 Level 2 Level 3 Total Fair Value Available-for-sale investment securities: U.S. Treasury and agency securities $ 1,896,931 $ 126,822 $ 0 $ 2,023,753 Obligations of state and political subdivisions 0 459,154 0 459,154 Government agency mortgage-backed securities 0 382,477 0 382,477 Corporate debt securities 0 2,546 0 2,546 Government agency collateralized mortgage obligations 0 68,119 0 68,119 Total available-for-sale investment securities 1,896,931 1,039,118 0 2,936,049 Equity securities 432 0 0 432 Mortgage loans held for sale 0 83 0 83 Interest rate swap agreements asset 0 793 0 793 Interest rate swap agreements liability 0 (742 ) 0 (742 ) Total $ 1,897,363 $ 1,039,252 $ 0 $ 2,936,615
Assets and Liabilities Measured on a Non-Recurring Basis	The fair value information of assets and liabilities measured on a non-recurring basis presented below is not as of the period-end, but rather as of the date the fair value adjustment was recorded closest to the date presented. September 30, 2019 December 31, 2018 (000's omitted) Level 1 Level 2 Level 3 Total Fair Value Level 1 Level 2 Level 3 Total Fair Value Impaired loans $ 0 $ 0 $ 1,729 $ 1,729 $ 0 $ 0 $ 1,102 $ 1,102 Mortgage servicing rights 0 0 93 93 0 0 0 0 Other real estate owned 0 0 1,258 1,258 0 0 1,320 1,320 Total $ 0 $ 0 $ 3,080 $ 3,080 $ 0 $ 0 $ 2,422 $ 2,422
Significant Unobservable Inputs, Fair Value Valuation Techniques	The Company determines fair values based on quoted market values, where available, estimates of present values, or other valuation techniques. Those techniques are significantly affected by the assumptions used, including, but not limited to, the discount rate and estimates of future cash flows. In that regard, the derived fair value estimates cannot be substantiated by comparison to independent markets and, in many cases, may not be realized in immediate settlement of the instrument. The significant unobservable inputs used in the determination of fair value of assets classified as Level 3 on a recurring or non-recurring basis are as follows: (000's omitted) Fair Value at September 30, 2019 Valuation Technique Significant Unobservable Inputs Significant Unobservable Input Range (Weighted Average) Impaired loans $ 1,729 Fair value of collateral Estimated cost of disposal/market adjustment 9.0% - 40.4% (40.4 %) Other real estate owned 1,258 Fair value of collateral Estimated cost of disposal/market adjustment 0.5% - 77.4% (35.7 %) Mortgage servicing rights 93 Discounted cash flow Weighted average constant prepayment rate 43.0 % Weighted average discount rate 2.69 % Adequate compensation $7/loan (000's omitted) Fair Value at December 31, 2018 Valuation Technique Significant Unobservable Inputs Significant Unobservable Input Range (Weighted Average) Impaired loans $ 1,102 Fair value of collateral Estimated cost of disposal/market adjustment 9.0% - 35.4% (28.8 %) Other real estate owned 1,320 Fair value of collateral Estimated cost of disposal/market adjustment 9.0% - 69.3% (23.8 %)
Carrying Amounts and Estimated Fair Values of Other Financial Instruments	Certain financial instruments and all nonfinancial instruments are excluded from fair value disclosure requirements. Accordingly, the aggregate fair value amounts presented do not represent the underlying value of the Company. The carrying amounts and estimated fair values of the Company’s other financial instruments that are not accounted for at fair value at September 30, 2019 and December 31, 2018 are as follows: September 30, 2019 December 31, 2018 (000's omitted) Carrying Value Fair Value Carrying Value Fair Value Financial assets: Net loans $ 6,803,768 $ 6,971,242 $ 6,231,837 $ 6,247,939 Financial liabilities: Deposits 9,168,285 9,166,701 8,322,371 8,308,765 Short-term borrowings 0 0 54,400 54,400 Securities sold under agreement to repurchase, short-term 233,333 233,333 259,367 259,367 Other long-term debt 4,328 4,303 1,976 1,921 Subordinated notes payable 13,814 13,814 0 0 Subordinated debt held by unconsolidated subsidiary trusts 77,320 77,320 97,939 97,939

DERIVATIVE INSTRUMENTS (Tables)

DERIVATIVE INSTRUMENTS (Tables)	9 Months Ended
	Sep. 30, 2019
DERIVATIVE INSTRUMENTS [Abstract]
Amounts Related to Cumulative Basis Adjustments for Fair Value Hedges	As of September 30, 2019, the following amounts were recorded in the consolidated statement of condition related to cumulative basis adjustments for fair value hedges: (000’s omitted) Carrying Amount of the Hedged Assets Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of the Hedged Assets Line Item in the Consolidated Statement of Condition in Which the Hedged Item Is Included September 30, 2019 September 30, 2019 Loans $ 6,307 $ (347 )
Fair Value of Derivative Instruments	Fair values of derivative instruments as of September 30, 2019 are as follows: (000’s omitted) September 30, 2019 Derivative Assets Derivative Liabilities Consolidated Statement of Condition Location Fair Value Consolidated Statement of Condition Location Fair Value Derivatives designated as hedging instruments under Subtopic 815-20 Interest rate swaps Other assets $ 347 Derivatives not designated as hedging instruments under Subtopic 815-20 Interest rate swaps Other assets 748 Accrued interest and other liabilities $ 748 Total derivatives $ 1,095 $ 748

SEGMENT INFORMATION (Tables)

SEGMENT INFORMATION (Tables)	9 Months Ended
	Sep. 30, 2019
SEGMENT INFORMATION [Abstract]
Segment Reporting Information by Segment	Information about reportable segments and reconciliation of the information to the consolidated financial statements follows: (000's omitted) Banking Employee Benefit Services All Other Eliminations Consolidated Total Three Months Ended September 30, 2019 Net interest income $ 91,018 $ 209 $ 49 $ 0 $ 91,276 Provision for loan losses 1,751 0 0 0 1,751 Noninterest revenues 17,790 24,830 15,143 (669 ) 57,094 Amortization of intangible assets 1,439 1,667 854 0 3,960 Acquisition expenses 6,061 0 0 0 6,061 Other operating expenses 61,839 14,721 11,017 (669 ) 86,908 Income before income taxes $ 37,718 $ 8,651 $ 3,321 $ 0 $ 49,690 Assets $ 11,398,191 $ 201,442 $ 74,169 $ (76,505 ) $ 11,597,297 Goodwill $ 670,023 $ 83,275 $ 20,312 $ 0 $ 773,610 Core deposit intangibles & Other intangibles $ 17,872 $ 39,440 $ 9,763 $ 0 $ 67,075 Three Months Ended September 30, 2018 Net interest income $ 86,060 $ 102 $ 36 $ 0 $ 86,198 Provision for loan losses 2,215 0 0 0 2,215 Noninterest revenues 18,002 23,815 14,737 (763 ) 55,791 Amortization of intangible assets 1,535 1,970 922 0 4,427 Acquisition expenses (832 ) 0 0 0 (832 ) Other operating expenses 57,863 14,025 10,513 (763 ) 81,638 Income before income taxes $ 43,281 $ 7,922 $ 3,338 $ 0 $ 54,541 Assets $ 10,440,732 $ 205,565 $ 66,470 $ (53,200 ) $ 10,659,567 Goodwill $ 629,916 $ 83,275 $ 20,288 $ 0 $ 733,479 Core deposit intangibles & Other intangibles $ 20,111 $ 46,514 $ 11,596 $ 0 $ 78,221 (000's omitted) Banking Employee Benefit Services All Other Eliminations Consolidated Total Nine Months Ended September 30, 2019 Net interest income $ 265,860 $ 448 $ 127 $ 0 $ 266,435 Provision for loan losses 5,573 0 0 0 5,573 Noninterest revenues 57,059 73,919 44,749 (2,231 ) 173,496 Amortization of intangible assets 4,297 5,105 2,592 0 11,994 Acquisition expenses 7,789 0 0 0 7,789 Other operating expenses 182,186 43,985 33,034 (2,231 ) 256,974 Income before income taxes $ 123,074 $ 25,277 $ 9,250 $ 0 $ 157,601 Nine Months Ended September 30, 2018 Net interest income $ 257,313 $ 264 $ 91 $ 0 $ 257,668 Provision for loan losses 8,342 0 0 0 8,342 Noninterest revenues 58,399 70,316 43,285 (2,159 ) 169,841 Amortization of intangible assets 4,914 6,047 2,819 0 13,780 Acquisition expenses (782 ) 7 6 0 (769 ) Other operating expenses 172,283 41,938 32,603 (2,159 ) 244,665 Income before income taxes $ 130,955 $ 22,588 $ 7,948 $ 0 $ 161,491

ACQUISITIONS (Details)

ACQUISITIONS (Details) $ in Thousands	Oct. 21, 2019USD ($)CountyBranch	Sep. 18, 2019USD ($)	Jul. 12, 2019USD ($)CountyBranch	Jan. 02, 2019USD ($)	Apr. 02, 2018USD ($)	Jan. 02, 2018USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2018USD ($)	Dec. 31, 2018USD ($)
Acquisitions [Abstract]
Cash		$ 500	$ 95,034				$ 4,653	$ 1,737
Goodwill			40,107				$ 773,610	$ 733,479	$ 733,503
Customer Lists [Member]
Acquisitions [Abstract]
Intangibles		$ 500
Steuben Trust Corporation [Member] | Subsequent Event [Member]
Acquisitions [Abstract]
Cash	$ 106,800
Number of branch locations added upon merger | Branch	15
Steuben Trust Corporation [Member] | Western New York State [Member] | Subsequent Event [Member]
Acquisitions [Abstract]
Number of counties where the bank has facilities | County	4
Number of new counties where the bank has extended footprints | County	2
Kinderhook Bank Corp [Member]
Acquisitions [Abstract]
Cash			$ 93,384
Number of branch locations added upon merger | Branch			11
Goodwill			$ 40,107
Kinderhook Bank Corp [Member] | Upstate New York [Member]
Acquisitions [Abstract]
Number of counties where the bank has facilities | County			5
Assets acquired			$ 642,900
Investment securities			39,800
Revenues			4,300
Direct expenses			$ 1,800
Wealth Resources Network, Inc [Member]
Acquisitions [Abstract]
Cash				$ 1,200
Wealth Resources Network, Inc [Member] | Customer Lists [Member]
Acquisitions [Abstract]
Intangibles				$ 1,200
HR Consultants (SA), LLC [Member]
Acquisitions [Abstract]
Cash					$ 300
HR Consultants (SA), LLC [Member] | Customer Lists [Member]
Acquisitions [Abstract]
Intangibles					$ 300
Penna & Associates Agency, Inc. [Member]
Acquisitions [Abstract]
Cash						$ 800
Goodwill						300
Penna & Associates Agency, Inc. [Member] | Customer Lists [Member]
Acquisitions [Abstract]
Intangibles						300
Styles Bridges Associates [Member]
Acquisitions [Abstract]
Cash						700
Styles Bridges Associates [Member] | Customer Lists [Member]
Acquisitions [Abstract]
Intangibles						$ 700

ACQUISITIONS, Estimated Fair Va

ACQUISITIONS, Estimated Fair Value of Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Sep. 18, 2019	Jul. 12, 2019		Apr. 02, 2018	[2]	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Consideration paid [Abstract]
Cash	$ 500	$ 95,034				$ 4,653	$ 1,737
Total net consideration paid		95,034
Recognized amounts of identifiable assets acquired and liabilities assumed [Abstract]
Cash and cash equivalents		90,381
Available-for-sale investment securities		37,653
Equity and other securities		2,117
Loans		479,931
Premises and equipment		13,970
Accrued interest and fees receivable		1,119
Other assets		14,144
Deposits		(568,081)
Other liabilities		(3,217)
Subordinated notes payable		(13,831)
Other long-term debt		(2,420)
Subordinated debt held by unconsolidated subsidiary trusts		(2,062)
Total identifiable assets, net		54,927
Goodwill		40,107				$ 773,610	$ 733,479	$ 733,503
Core Deposit Intangibles [Member]
Recognized amounts of identifiable assets acquired and liabilities assumed [Abstract]
Intangibles		3,573
Other Intangibles [Member]
Recognized amounts of identifiable assets acquired and liabilities assumed [Abstract]
Intangibles		1,650
Kinderhook Bank Corp [Member]
Consideration paid [Abstract]
Cash		93,384
Total net consideration paid		93,384
Recognized amounts of identifiable assets acquired and liabilities assumed [Abstract]
Cash and cash equivalents		90,381
Available-for-sale investment securities		37,653
Equity and other securities		2,117
Loans		479,931
Premises and equipment		13,970
Accrued interest and fees receivable		1,119
Other assets		14,144
Deposits		(568,081)
Other liabilities		(3,217)
Subordinated notes payable		(13,831)
Other long-term debt		(2,420)
Subordinated debt held by unconsolidated subsidiary trusts		(2,062)
Total identifiable assets, net		53,277
Goodwill		40,107
Kinderhook Bank Corp [Member] | Core Deposit Intangibles [Member]
Recognized amounts of identifiable assets acquired and liabilities assumed [Abstract]
Intangibles		3,573
Kinderhook Bank Corp [Member] | Other Intangibles [Member]
Recognized amounts of identifiable assets acquired and liabilities assumed [Abstract]
Intangibles		0
Other [Member]
Consideration paid [Abstract]
Cash		1,650	[1]	$ 1,753
Total net consideration paid		1,650	[1]	1,753
Recognized amounts of identifiable assets acquired and liabilities assumed [Abstract]
Cash and cash equivalents		0	[1]	16
Available-for-sale investment securities		0	[1]	0
Equity and other securities		0	[1]	0
Loans		0	[1]	0
Premises and equipment		0	[1]	10
Accrued interest and fees receivable		0	[1]	0
Other assets		0	[1]	105
Deposits		0	[1]	0
Other liabilities		0	[1]	(31)
Subordinated notes payable		0	[1]	0
Other long-term debt		0	[1]	0
Subordinated debt held by unconsolidated subsidiary trusts		0	[1]	0
Total identifiable assets, net		1,650	[1]	1,443
Goodwill		0	[1]	310
Other [Member] | Core Deposit Intangibles [Member]
Recognized amounts of identifiable assets acquired and liabilities assumed [Abstract]
Intangibles		0	[1]	0
Other [Member] | Other Intangibles [Member]
Recognized amounts of identifiable assets acquired and liabilities assumed [Abstract]
Intangibles		$ 1,650	[1]	$ 1,343
[1]	Includes amounts related to both acquisitions completed by CISI in 2019.
[2]	Includes amounts related to the Styles Bridges, Penna, and HR Consultants acquisitions.

ACQUISITIONS, Summary of Loans

ACQUISITIONS, Summary of Loans Acquired (Details) - Kinderhook Bank Corp [Member] $ in Thousands	Jul. 12, 2019USD ($)
Summary of loans acquired [Abstract]
Contractually required principal and interest at acquisition	$ 604,355
Contractual cash flows not expected to be collected	(9,568)
Expected cash flows at acquisition	594,787
Interest component of expected cash flows	(114,856)
Fair value of acquired loans	479,931
Acquired Impaired Loans [Member]
Summary of loans acquired [Abstract]
Contractually required principal and interest at acquisition	12,661
Contractual cash flows not expected to be collected	(4,096)
Expected cash flows at acquisition	8,565
Interest component of expected cash flows	(512)
Fair value of acquired loans	8,053
Acquired Non Impaired Loans [Member]
Summary of loans acquired [Abstract]
Contractually required principal and interest at acquisition	591,694
Contractual cash flows not expected to be collected	(5,472)
Expected cash flows at acquisition	586,222
Interest component of expected cash flows	(114,344)
Fair value of acquired loans	$ 471,878

ACQUISITIONS, Intangible Asset,

ACQUISITIONS, Intangible Asset, Goodwill and Acquisition-related Expenses (Details) - USD ($) $ in Thousands	Jul. 12, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Fair Value of Subordinated Notes Payable [Abstract]
Subordinated notes		$ 13,814		$ 13,814		$ 0
Summary of loans acquired [Abstract]
Merger and acquisition integration related (recoveries) expenses		$ 6,061	$ (832)	$ 7,789	$ (769)
Subordinated Notes Maturing in February 2028 [Member]
Fair Value of Subordinated Notes Payable [Abstract]
Subordinated notes	$ 3,000
Fixed interest rate percentage	6.00%
Maturity date	Feb. 29, 2028
Subordinated Notes Maturing in November 2025 [Member]
Fair Value of Subordinated Notes Payable [Abstract]
Subordinated notes	$ 10,000
Fixed interest rate percentage	6.375%
Maturity date	Nov. 30, 2025
Kinderhook Bank Corp [Member] | Core Deposits [Member]
Intangible Assets [Abstract]
Estimated useful life				8 years
Kinderhook Bank Corp [Member] | Other Intangibles [Member]
Intangible Assets [Abstract]
Estimated useful life				8 years
Wealth Resources Network, Inc [Member] | Core Deposits [Member]
Intangible Assets [Abstract]
Estimated useful life				8 years
Wealth Resources Network, Inc [Member] | Other Intangibles [Member]
Intangible Assets [Abstract]
Estimated useful life				8 years
Sageer [Member] | Core Deposits [Member]
Intangible Assets [Abstract]
Estimated useful life				8 years
Sageer [Member] | Other Intangibles [Member]
Intangible Assets [Abstract]
Estimated useful life				8 years
Styles Bridges Associates [Member] | Core Deposits [Member]
Intangible Assets [Abstract]
Estimated useful life				8 years
Styles Bridges Associates [Member] | Other Intangibles [Member]
Intangible Assets [Abstract]
Estimated useful life				8 years
Penna & Associates Agency, Inc. [Member] | Core Deposits [Member]
Intangible Assets [Abstract]
Estimated useful life				8 years
Penna & Associates Agency, Inc. [Member] | Other Intangibles [Member]
Intangible Assets [Abstract]
Estimated useful life				8 years
HR Consultants (SA), LLC [Member] | Core Deposits [Member]
Intangible Assets [Abstract]
Estimated useful life				8 years
HR Consultants (SA), LLC [Member] | Other Intangibles [Member]
Intangible Assets [Abstract]
Estimated useful life				8 years

ACQUISITIONS, Supplemental Pro

ACQUISITIONS, Supplemental Pro Forma Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Supplemental Pro Forma Financial Information [Abstract]
Total revenue, net of interest expense, pro forma	$ 149,087	$ 148,152	$ 452,995	$ 446,084
Net income, pro forma	$ 44,154	$ 44,313	$ 135,370	$ 125,505

ACCOUNTING POLICIES (Details)

ACCOUNTING POLICIES (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Contract Balances [Abstract]
Accounts receivable		$ 28,000		$ 26,400
Unbilled fee revenue		8,300		7,800
Unearned revenue		1,900		2,200
Recently Adopted Accounting Pronouncements [Abstract]
Right to use assets		41,948
Lease liability		42,769
Allowance for loan losses		49,423	$ 49,310	49,284	$ 50,133	$ 49,618	$ 47,583
ASU 2016-02 [Member]
Recently Adopted Accounting Pronouncements [Abstract]
Right to use assets				34,200
Lease liability				$ 34,200
ASU 2016-13 [Member]
Recently Adopted Accounting Pronouncements [Abstract]
Allowance for loan losses		$ 49,400
ASU 2016-13 [Member] | Forecast [Member] | Minimum [Member]
Recently Adopted Accounting Pronouncements [Abstract]
Allowance for credit losses	$ 52,000
Percentage increase over allowance for loan losses	5.00%
ASU 2016-13 [Member] | Forecast [Member] | Maximum [Member]
Recently Adopted Accounting Pronouncements [Abstract]
Allowance for credit losses	$ 60,000
Percentage increase over allowance for loan losses	21.00%

INVESTMENT SECURITIES, Availabl

INVESTMENT SECURITIES, Available-for-Sale Portfolio (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Available-for-Sale Portfolio [Abstract]
Amortized cost	$ 2,392,004	$ 2,952,278
Gross unrealized gains	46,203	10,339
Gross unrealized losses	1,105	26,568
Fair value	2,437,102	2,936,049
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized cost	2,392,004
Fair value	2,437,102
U.S. Treasury and Agency Securities [Member]
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized cost	1,482,739	2,036,474
Gross unrealized gains	24,122	2,190
Gross unrealized losses	214	14,911
Fair value	1,506,647	2,023,753
Obligations of State and Political Subdivisions [Member]
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized cost	442,942	453,640
Gross unrealized gains	15,159	6,563
Gross unrealized losses	11	1,049
Fair value	458,090	459,154
Government Agency Mortgage-Backed Securities [Member]
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized cost	406,329	390,234
Gross unrealized gains	6,330	1,526
Gross unrealized losses	843	9,283
Fair value	411,816	382,477
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized cost	2,542	2,588
Gross unrealized gains	0	0
Gross unrealized losses	2	42
Fair value	2,540	2,546
Government Agency Collateralized Mortgage Obligations [Member]
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized cost	57,452	69,342
Gross unrealized gains	592	60
Gross unrealized losses	35	1,283
Fair value	$ 58,009	$ 68,119

INVESTMENT SECURITIES, Equity a

INVESTMENT SECURITIES, Equity and Other Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Equity and Other Securities [Abstract]
Amortized cost	$ 43,680	$ 44,678
Gross unrealized gains	960	950
Gross unrealized losses		19
Fair value	44,640	45,609
Equity Securities, at Fair Value [Abstract]
Amortized cost	251	251
Gross unrealized gains	210	200
Gross unrealized losses		19
Fair value	461	432
Federal Home Loan Bank Common Stock [Member]
Other Equity Securities, at Adjusted Cost [Abstract]
Amortized cost	6,912	8,768
Fair value	6,912	8,768
Federal Reserve Bank Common Stock [Member]
Other Equity Securities, at Adjusted Cost [Abstract]
Amortized cost	31,992	30,690
Fair value	31,992	30,690
Other Equity Securities [Member]
Other Equity Securities, at Adjusted Cost [Abstract]
Amortized cost	4,525	4,969
Gross unrealized gains	750	750
Fair value	$ 5,275	$ 5,719

INVESTMENT SECURITIES, Investme

INVESTMENT SECURITIES, Investment Securities in a Continuous Unrealized Loss Position (Details) $ in Thousands	Sep. 30, 2019USD ($)Position	Dec. 31, 2018USD ($)Position
Available-for-Sale Portfolio in Unrealized Loss Positions, Number of Positions [Abstract]
Less than 12 months | Position	108	169
12 months or longer | Position	75	384
Total | Position	183	553
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	$ 125,779	$ 576,527
12 months or longer	174,210	1,584,618
Total	299,989	2,161,145
Available-for-Sale Portfolio, Debt Maturities, Gross Unrealized Losses [Abstract]
Less than 12 months	173	1,156
12 months or longer	932	25,412
Total	$ 1,105	$ 26,568
Equity and Other Securities, Continuous Unrealized Loss Position, Number of Positions [Abstract]
Less than 12 months | Position		1
12 months or longer | Position		0
Total | Position		1
Equity and Other Securities, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months		$ 82
12 months or longer		0
Total		82
Equity and Other Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses [Abstract]
Less than 12 months		19
12 months or longer		0
Total		$ 19
U.S. Treasury and Agency Securities [Member]
Available-for-Sale Portfolio in Unrealized Loss Positions, Number of Positions [Abstract]
Less than 12 months | Position	6	7
12 months or longer | Position	12	64
Total | Position	18	71
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	$ 77,332	$ 473,082
12 months or longer	107,840	1,213,276
Total	185,172	1,686,358
Available-for-Sale Portfolio, Debt Maturities, Gross Unrealized Losses [Abstract]
Less than 12 months	58	682
12 months or longer	156	14,229
Total	$ 214	$ 14,911
Obligations of State and Political Subdivisions [Member]
Available-for-Sale Portfolio in Unrealized Loss Positions, Number of Positions [Abstract]
Less than 12 months | Position	73	118
12 months or longer | Position	0	97
Total | Position	73	215
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	$ 7,125	$ 55,671
12 months or longer	0	51,753
Total	7,125	107,424
Available-for-Sale Portfolio, Debt Maturities, Gross Unrealized Losses [Abstract]
Less than 12 months	11	216
12 months or longer	0	833
Total	$ 11	$ 1,049
Government Agency Mortgage-Backed Securities [Member]
Available-for-Sale Portfolio in Unrealized Loss Positions, Number of Positions [Abstract]
Less than 12 months | Position	24	43
12 months or longer | Position	55	181
Total | Position	79	224
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	$ 34,660	$ 47,708
12 months or longer	58,473	253,931
Total	93,133	301,639
Available-for-Sale Portfolio, Debt Maturities, Gross Unrealized Losses [Abstract]
Less than 12 months	95	258
12 months or longer	748	9,025
Total	$ 843	$ 9,283
Corporate Debt Securities [Member]
Available-for-Sale Portfolio in Unrealized Loss Positions, Number of Positions [Abstract]
Less than 12 months | Position	0	0
12 months or longer | Position	1	1
Total | Position	1	1
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	$ 0	$ 0
12 months or longer	2,540	2,546
Total	2,540	2,546
Available-for-Sale Portfolio, Debt Maturities, Gross Unrealized Losses [Abstract]
Less than 12 months	0	0
12 months or longer	2	42
Total	$ 2	$ 42
Government Agency Collateralized Mortgage Obligations [Member]
Available-for-Sale Portfolio in Unrealized Loss Positions, Number of Positions [Abstract]
Less than 12 months | Position	5	1
12 months or longer | Position	7	41
Total | Position	12	42
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months	$ 6,662	$ 66
12 months or longer	5,357	63,112
Total	12,019	63,178
Available-for-Sale Portfolio, Debt Maturities, Gross Unrealized Losses [Abstract]
Less than 12 months	9	0
12 months or longer	26	1,283
Total	$ 35	$ 1,283
Equity Securities, at Fair Value [Member]
Equity and Other Securities, Continuous Unrealized Loss Position, Number of Positions [Abstract]
Less than 12 months | Position		1
12 months or longer | Position		0
Total | Position		1
Equity and Other Securities, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months		$ 82
12 months or longer		0
Total		82
Equity and Other Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses [Abstract]
Less than 12 months		19
12 months or longer		0
Total		$ 19

INVESTMENT SECURITIES, Amortize

INVESTMENT SECURITIES, Amortized Cost and Estimated Fair Value of Debt Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Available-for-Sale, Debt Maturities, Amortized Cost [Abstract]
Due in one year or less	$ 71,512
Due after one through five years	1,512,018
Due after five years through ten years	54,176
Due after ten years	290,517
Subtotal	1,928,223
Amortized cost	2,392,004
Available-for-Sale, Debt Maturities, Fair Value [Abstract]
Due in one year or less	71,510
Due after one through five years	1,538,064
Due after five years through ten years	58,251
Due after ten years	299,452
Subtotal	1,967,277
Fair value	2,437,102
Government Agency Mortgage-Backed Securities [Member]
Available-for-Sale, Debt Maturities, Amortized Cost [Abstract]
Without single maturity date	406,329
Amortized cost	406,329	$ 390,234
Available-for-Sale, Debt Maturities, Fair Value [Abstract]
Without single maturity date	411,816
Fair value	411,816	382,477
Government Agency Collateralized Mortgage Obligations [Member]
Available-for-Sale, Debt Maturities, Amortized Cost [Abstract]
Without single maturity date	57,452
Amortized cost	57,452	69,342
Available-for-Sale, Debt Maturities, Fair Value [Abstract]
Without single maturity date	58,009
Fair value	$ 58,009	$ 68,119

INVESTMENT SECURITIES, Invest_2

INVESTMENT SECURITIES, Investment Securities Pledged as Collateral (Details) $ in Millions	Sep. 30, 2019USD ($)
U.S. Treasury Securities [Member] | Securities Sold under Agreements to Repurchase [Member]
Investment Securities Pledged as Collateral [Abstract]
Investment securities pledged to collateralize certain deposits and borrowings	$ 245.6

INVESTMENT SECURITIES, Proceeds

INVESTMENT SECURITIES, Proceeds from Sales of Securities (Details) - U.S. Treasury Securities [Member] $ in Millions	9 Months Ended
	Sep. 30, 2019USD ($)
Proceeds from sales of securities [Abstract]
Proceeds from sales of securities	$ 590.2
Gross realized gains	5
Gross realized losses	$ 0.1

LOANS, Loan Summary (Details)

LOANS, Loan Summary (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Loans receivable, net [Abstract]
Gross loans, including deferred origination costs	$ 6,853,191		$ 6,281,121
Allowance for loan losses	(49,423)	$ (49,310)	(49,284)	$ (50,133)	$ (49,618)	$ (47,583)
Net loans	6,803,768		6,231,837
Credit impaired acquired loans, total balance due	16,700		7,400
Accretable discount related to credit impaired acquired loans [Roll forward]
Beginning Balance	437
Accretion recognized, year-to-date	(302)
Net reclassification from non-accretable to accretable	96
Kinderhook acquisition	512
Ending Balance	743
Business Lending [Member]
Loans receivable, net [Abstract]
Gross loans, including deferred origination costs	$ 2,779,612		2,396,977
Consumer Mortgage [Member] | Minimum [Member]
Loans receivable, net [Abstract]
Typical contract term	10 years
Consumer Mortgage [Member] | Maximum [Member]
Loans receivable, net [Abstract]
Typical contract term	30 years
Home Equity [Member] | Maximum [Member]
Loans receivable, net [Abstract]
Typical contract term	30 years
Commercial Portfolio Segment [Member] | Business Lending [Member]
Loans receivable, net [Abstract]
Gross loans, including deferred origination costs	$ 2,779,612		2,396,977
Commercial Portfolio Segment [Member] | Consumer Mortgage [Member]
Loans receivable, net [Abstract]
Allowance for loan losses	(10,477)	(10,763)	(10,124)	(10,170)	(10,473)	(10,465)
Residential Portfolio Segment [Member] | Business Lending [Member]
Loans receivable, net [Abstract]
Allowance for loan losses	(18,055)	(17,769)	(18,522)	(18,780)	(18,439)	(17,257)
Residential Portfolio Segment [Member] | Consumer Mortgage [Member]
Loans receivable, net [Abstract]
Gross loans, including deferred origination costs	2,405,191		2,235,408
Consumer Portfolio Segment [Member] | Consumer Indirect [Member]
Loans receivable, net [Abstract]
Gross loans, including deferred origination costs	1,091,980		1,083,207
Allowance for loan losses	(14,437)	(14,345)	(14,366)	(14,969)	(14,424)	(13,468)
Consumer Portfolio Segment [Member] | Consumer Direct [Member]
Loans receivable, net [Abstract]
Gross loans, including deferred origination costs	187,379		178,820
Allowance for loan losses	(3,278)	(3,184)	(3,095)	(3,221)	(3,164)	(3,039)
Consumer Portfolio Segment [Member] | Home Equity [Member]
Loans receivable, net [Abstract]
Gross loans, including deferred origination costs	389,029		386,709
Allowance for loan losses	$ (2,082)	$ (2,103)	$ (2,144)	$ (2,034)	$ (2,015)	$ (2,107)

LOANS, Credit Quality By Past D

LOANS, Credit Quality By Past Due Status (Details) - USD ($) $ in Thousands		Sep. 30, 2019	Dec. 31, 2018
Aged analysis of the company's loans [Abstract]
Total loans		$ 6,853,191	$ 6,281,121
Legacy Loans [Member]
Aged analysis of the company's loans [Abstract]
90 + days past due and still accruing		3,734	2,106
Nonaccrual		16,644	16,182
Total past due		46,962	53,387
Current		5,260,327	4,974,597
Total loans		5,307,289	5,027,984
Legacy Loans [Member] | Past Due 30 - 89 Days [Member]
Aged analysis of the company's loans [Abstract]
Total past due		26,584	35,099
Acquired Loans [Member]
Aged analysis of the company's loans [Abstract]
90 + days past due and still accruing		1,330	349
Nonaccrual		6,966	6,362
Total past due		11,014	9,332
Acquired impaired	[1]	11,508	5,446
Current		1,523,380	1,238,359
Total loans		1,545,902	1,253,137
Acquired Loans [Member] | Past Due 30 - 89 Days [Member]
Aged analysis of the company's loans [Abstract]
Total past due		2,718	2,621
Business Lending [Member]
Aged analysis of the company's loans [Abstract]
Total loans		2,779,612	2,396,977
Business Lending [Member] | Legacy Loans [Member]
Aged analysis of the company's loans [Abstract]
Total loans		1,786,072	1,618,827
Business Lending [Member] | Acquired Loans [Member]
Aged analysis of the company's loans [Abstract]
Total loans		993,540	778,150
Consumer Mortgage [Member] | Legacy Loans [Member]
Aged analysis of the company's loans [Abstract]
Total loans		1,945,929	1,848,450
Consumer Mortgage [Member] | Acquired Loans [Member]
Aged analysis of the company's loans [Abstract]
Total loans		459,262	386,958
Consumer Indirect [Member] | Legacy Loans [Member]
Aged analysis of the company's loans [Abstract]
Total loans		1,085,333	1,072,392
Consumer Indirect [Member] | Acquired Loans [Member]
Aged analysis of the company's loans [Abstract]
Total loans		6,647	10,815
Consumer Direct [Member] | Legacy Loans [Member]
Aged analysis of the company's loans [Abstract]
Total loans		178,326	175,774
Consumer Direct [Member] | Acquired Loans [Member]
Aged analysis of the company's loans [Abstract]
Total loans		9,053	3,046
Home Equity [Member] | Legacy Loans [Member]
Aged analysis of the company's loans [Abstract]
Total loans		311,629	312,541
Home Equity [Member] | Acquired Loans [Member]
Aged analysis of the company's loans [Abstract]
Total loans		77,400	74,168
Commercial Portfolio Segment [Member] | Business Lending [Member]
Aged analysis of the company's loans [Abstract]
Total loans		2,779,612	2,396,977
Commercial Portfolio Segment [Member] | Business Lending [Member] | Legacy Loans [Member]
Aged analysis of the company's loans [Abstract]
90 + days past due and still accruing		189	179
Nonaccrual		4,590	4,872
Total past due		7,476	10,312
Current		1,778,596	1,608,515
Total loans		1,786,072	1,618,827
Commercial Portfolio Segment [Member] | Business Lending [Member] | Legacy Loans [Member] | Past Due 30 - 89 Days [Member]
Aged analysis of the company's loans [Abstract]
Total past due		2,697	5,261
Commercial Portfolio Segment [Member] | Business Lending [Member] | Acquired Loans [Member]
Aged analysis of the company's loans [Abstract]
90 + days past due and still accruing		997	0
Nonaccrual		3,957	3,498
Total past due		5,701	4,472
Acquired impaired	[1]	11,508	5,446
Current		976,331	768,232
Total loans		993,540	778,150
Commercial Portfolio Segment [Member] | Business Lending [Member] | Acquired Loans [Member] | Past Due 30 - 89 Days [Member]
Aged analysis of the company's loans [Abstract]
Total past due		747	974
Residential Portfolio Segment [Member] | Consumer Mortgage [Member]
Aged analysis of the company's loans [Abstract]
Total loans		2,405,191	2,235,408
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] | Legacy Loans [Member]
Aged analysis of the company's loans [Abstract]
90 + days past due and still accruing		2,976	1,393
Nonaccrual		10,650	9,872
Total past due		24,664	23,733
Current		1,921,265	1,824,717
Total loans		1,945,929	1,848,450
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] | Legacy Loans [Member] | Past Due 30 - 89 Days [Member]
Aged analysis of the company's loans [Abstract]
Total past due		11,038	12,468
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] | Acquired Loans [Member]
Aged analysis of the company's loans [Abstract]
90 + days past due and still accruing		171	232
Nonaccrual		2,409	2,390
Total past due		4,153	3,463
Acquired impaired	[1]	0	0
Current		455,109	383,495
Total loans		459,262	386,958
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] | Acquired Loans [Member] | Past Due 30 - 89 Days [Member]
Aged analysis of the company's loans [Abstract]
Total past due		1,573	841
Consumer Portfolio Segment [Member] | Consumer Indirect [Member]
Aged analysis of the company's loans [Abstract]
Total loans		1,091,980	1,083,207
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] | Legacy Loans [Member]
Aged analysis of the company's loans [Abstract]
90 + days past due and still accruing		177	258
Nonaccrual		0	0
Total past due		10,484	14,867
Current		1,074,849	1,057,525
Total loans		1,085,333	1,072,392
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] | Legacy Loans [Member] | Past Due 30 - 89 Days [Member]
Aged analysis of the company's loans [Abstract]
Total past due		10,307	14,609
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] | Acquired Loans [Member]
Aged analysis of the company's loans [Abstract]
90 + days past due and still accruing		32	34
Nonaccrual		0	0
Total past due		65	112
Acquired impaired	[1]	0	0
Current		6,582	10,703
Total loans		6,647	10,815
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] | Acquired Loans [Member] | Past Due 30 - 89 Days [Member]
Aged analysis of the company's loans [Abstract]
Total past due		33	78
Consumer Portfolio Segment [Member] | Consumer Direct [Member]
Aged analysis of the company's loans [Abstract]
Total loans		187,379	178,820
Consumer Portfolio Segment [Member] | Consumer Direct [Member] | Legacy Loans [Member]
Aged analysis of the company's loans [Abstract]
90 + days past due and still accruing		38	48
Nonaccrual		0	0
Total past due		1,084	1,826
Current		177,242	173,948
Total loans		178,326	175,774
Consumer Portfolio Segment [Member] | Consumer Direct [Member] | Legacy Loans [Member] | Past Due 30 - 89 Days [Member]
Aged analysis of the company's loans [Abstract]
Total past due		1,046	1,778
Consumer Portfolio Segment [Member] | Consumer Direct [Member] | Acquired Loans [Member]
Aged analysis of the company's loans [Abstract]
90 + days past due and still accruing		5	4
Nonaccrual		54	0
Total past due		145	119
Acquired impaired	[1]	0	0
Current		8,908	2,927
Total loans		9,053	3,046
Consumer Portfolio Segment [Member] | Consumer Direct [Member] | Acquired Loans [Member] | Past Due 30 - 89 Days [Member]
Aged analysis of the company's loans [Abstract]
Total past due		86	115
Consumer Portfolio Segment [Member] | Home Equity [Member]
Aged analysis of the company's loans [Abstract]
Total loans		389,029	386,709
Consumer Portfolio Segment [Member] | Home Equity [Member] | Legacy Loans [Member]
Aged analysis of the company's loans [Abstract]
90 + days past due and still accruing		354	228
Nonaccrual		1,404	1,438
Total past due		3,254	2,649
Current		308,375	309,892
Total loans		311,629	312,541
Consumer Portfolio Segment [Member] | Home Equity [Member] | Legacy Loans [Member] | Past Due 30 - 89 Days [Member]
Aged analysis of the company's loans [Abstract]
Total past due		1,496	983
Consumer Portfolio Segment [Member] | Home Equity [Member] | Acquired Loans [Member]
Aged analysis of the company's loans [Abstract]
90 + days past due and still accruing		125	79
Nonaccrual		546	474
Total past due		950	1,166
Acquired impaired	[1]	0	0
Current		76,450	73,002
Total loans		77,400	74,168
Consumer Portfolio Segment [Member] | Home Equity [Member] | Acquired Loans [Member] | Past Due 30 - 89 Days [Member]
Aged analysis of the company's loans [Abstract]
Total past due		$ 279	$ 613
[1]	Acquired impaired loans were not classified as nonperforming assets as the loans are considered to be performing under ASC 310-30.  As a result interest income, through the accretion of the difference between the carrying amount of the loans and the expected cashflows, is being recognized on all acquired impaired loans.

LOANS, Amount of Business Lendi

LOANS, Amount of Business Lending Loans by Credit Quality Category (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Business Lending Loans by Credit Quality Category [Abstract]
Loans	$ 6,853,191	$ 6,281,121
Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	5,307,289	5,027,984
Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	1,545,902	1,253,137
Business Lending [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	2,779,612	2,396,977
Business Lending [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	1,786,072	1,618,827
Business Lending [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	993,540	778,150
Business Lending [Member] | Pass [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	2,495,745	2,141,830
Business Lending [Member] | Pass [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	1,609,382	1,439,337
Business Lending [Member] | Pass [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	886,363	702,493
Business Lending [Member] | Special Mention [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	152,448	145,172
Business Lending [Member] | Special Mention [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	91,159	105,065
Business Lending [Member] | Special Mention [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	61,289	40,107
Business Lending [Member] | Classified [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	119,911	102,950
Business Lending [Member] | Classified [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	85,531	74,425
Business Lending [Member] | Classified [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	34,380	28,525
Business Lending [Member] | Doubtful [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	0	1,579
Business Lending [Member] | Doubtful [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	0	0
Business Lending [Member] | Doubtful [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	0	1,579
Business Lending [Member] | Acquired Impaired [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	11,508	5,446
Business Lending [Member] | Acquired Impaired [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	0	0
Business Lending [Member] | Acquired Impaired [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	11,508	5,446
All Other Loans [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	3,521,217	3,409,157
All Other Loans [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	552,362	474,987
All Other Loans [Member] | Performing [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	3,505,618	3,395,920
All Other Loans [Member] | Performing [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	549,020	471,774
All Other Loans [Member] | Nonperforming [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	15,599	13,237
All Other Loans [Member] | Nonperforming [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	3,342	3,213
Consumer Mortgage [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	1,945,929	1,848,450
Consumer Mortgage [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	459,262	386,958
Consumer Mortgage [Member] | Performing [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	1,932,303	1,837,185
Consumer Mortgage [Member] | Performing [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	456,682	384,336
Consumer Mortgage [Member] | Nonperforming [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	13,626	11,265
Consumer Mortgage [Member] | Nonperforming [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	2,580	2,622
Consumer Indirect [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	1,085,333	1,072,392
Consumer Indirect [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	6,647	10,815
Consumer Indirect [Member] | Performing [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	1,085,156	1,072,134
Consumer Indirect [Member] | Performing [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	6,615	10,781
Consumer Indirect [Member] | Nonperforming [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	177	258
Consumer Indirect [Member] | Nonperforming [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	32	34
Consumer Direct [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	178,326	175,774
Consumer Direct [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	9,053	3,046
Consumer Direct [Member] | Performing [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	178,288	175,726
Consumer Direct [Member] | Performing [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	8,994	3,042
Consumer Direct [Member] | Nonperforming [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	38	48
Consumer Direct [Member] | Nonperforming [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	59	4
Home Equity [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	311,629	312,541
Home Equity [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	77,400	74,168
Home Equity [Member] | Performing [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	309,871	310,875
Home Equity [Member] | Performing [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	76,729	73,615
Home Equity [Member] | Nonperforming [Member] | Legacy Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	1,758	1,666
Home Equity [Member] | Nonperforming [Member] | Acquired Loans [Member]
Business Lending Loans by Credit Quality Category [Abstract]
Loans	$ 671	$ 553

LOANS, Summary of Impaired Loan

LOANS, Summary of Impaired Loans, Excluding Purchased Impaired (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Impaired loans [Abstract]
Loans with allowance allocation	$ 0	$ 3,956
Loans without allowance allocation	5,172	2,230
Carrying balance	5,172	6,186
Contractual balance	11,896	12,078
Specifically allocated allowance	$ 0	$ 956

LOANS, Troubled Debt Restructur

LOANS, Troubled Debt Restructurings (TDRs) (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019USD ($)Loan	Sep. 30, 2018USD ($)Loan	Sep. 30, 2019USD ($)Loan	Sep. 30, 2018USD ($)Loan	Dec. 31, 2018USD ($)Loan
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	237		237		218
TDRs, amount	$ 6,824		$ 6,824		$ 5,525
Loans modified in TDR during the year, number | Loan	21	21	53	39
Loans modified in TDR during the year, amount	$ 1,020	$ 322	$ 2,244	$ 782
Maximum [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
Threshold balance of TDR loans collectively included in general loan loss allocation and qualitative review	$ 500		$ 500
Nonaccrual [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	75		75		62
TDRs, amount	$ 3,419		$ 3,419		$ 2,388
Accruing [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	162		162		156
TDRs, amount	$ 3,405		$ 3,405		$ 3,137
Commercial Portfolio Segment [Member] | Minimum [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
Threshold balance of loans individually evaluated for impairment	$ 500		$ 500
Commercial Portfolio Segment [Member] | Business Lending [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	8		8		6
TDRs, amount	$ 867		$ 867		$ 327
Loans modified in TDR during the year, number | Loan	1	0	3	1
Loans modified in TDR during the year, amount	$ 415	$ 0	$ 660	$ 93
Commercial Portfolio Segment [Member] | Business Lending [Member] | Nonaccrual [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	5		5		4
TDRs, amount	$ 662		$ 662		$ 162
Commercial Portfolio Segment [Member] | Business Lending [Member] | Accruing [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	3		3		2
TDRs, amount	$ 205		$ 205		$ 165
Residential Portfolio Segment [Member] | Consumer Mortgage [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	106		106		92
TDRs, amount	$ 4,472		$ 4,472		$ 3,755
Loans modified in TDR during the year, number | Loan	8	4	19	7
Loans modified in TDR during the year, amount	$ 464	$ 195	$ 1,271	$ 407
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] | Nonaccrual [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	57		57		46
TDRs, amount	$ 2,527		$ 2,527		$ 1,986
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] | Accruing [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	49		49		46
TDRs, amount	$ 1,945		$ 1,945		$ 1,769
Consumer Portfolio Segment [Member] | Consumer Indirect [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	77		77		77
TDRs, amount	$ 854		$ 854		$ 857
Loans modified in TDR during the year, number | Loan	10	14	22	24
Loans modified in TDR during the year, amount	$ 116	$ 117	$ 206	$ 176
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] | Nonaccrual [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	0		0		0
TDRs, amount	$ 0		$ 0		$ 0
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] | Accruing [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	77		77		77
TDRs, amount	$ 854		$ 854		$ 857
Consumer Portfolio Segment [Member] | Consumer Direct [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	22		22		22
TDRs, amount	$ 91		$ 91		$ 71
Loans modified in TDR during the year, number | Loan	2	2	5	5
Loans modified in TDR during the year, amount	$ 25	$ 10	$ 35	$ 21
Consumer Portfolio Segment [Member] | Consumer Direct [Member] | Nonaccrual [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	0		0		0
TDRs, amount	$ 0		$ 0		$ 0
Consumer Portfolio Segment [Member] | Consumer Direct [Member] | Accruing [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	22		22		22
TDRs, amount	$ 91		$ 91		$ 71
Consumer Portfolio Segment [Member] | Home Equity [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	24		24		21
TDRs, amount	$ 540		$ 540		$ 515
Loans modified in TDR during the year, number | Loan	0	1	4	2
Loans modified in TDR during the year, amount	$ 0	$ 0	$ 72	$ 85
Consumer Portfolio Segment [Member] | Home Equity [Member] | Nonaccrual [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	13		13		12
TDRs, amount	$ 230		$ 230		$ 240
Consumer Portfolio Segment [Member] | Home Equity [Member] | Accruing [Member]
Troubled Debt Restructurings (TDRs) [Abstract]
TDRs, number | Loan	11		11		9
TDRs, amount	$ 310		$ 310		$ 275

LOANS, Allowance for Loan Losse

LOANS, Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Allowance for loan losses [Roll Forward]
Beginning balance	$ 49,310	$ 49,618	$ 49,284	$ 47,583
Charge-offs	(3,230)	(3,267)	(10,002)	(10,636)
Recoveries	1,592	1,567	4,568	4,844
Provision	1,751	2,215	5,573	8,342
Ending balance	49,423	50,133	49,423	50,133
Acquired Impaired [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	155	33	33	147
Charge-offs	0	0	0	(368)
Recoveries	0	0	0	0
Provision	1	15	123	269
Ending balance	156	48	156	48
Residential Portfolio Segment [Member] | Business Lending [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	17,769	18,439	18,522	17,257
Charge-offs	(305)	(73)	(1,774)	(2,000)
Recoveries	290	93	593	404
Provision	301	321	714	3,119
Ending balance	18,055	18,780	18,055	18,780
Commercial Portfolio Segment [Member] | Consumer Mortgage [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	10,763	10,473	10,124	10,465
Charge-offs	(200)	(144)	(1,040)	(588)
Recoveries	8	46	44	109
Provision	(94)	(205)	1,349	184
Ending balance	10,477	10,170	10,477	10,170
Consumer Portfolio Segment [Member] | Consumer Indirect [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	14,345	14,424	14,366	13,468
Charge-offs	(2,224)	(2,364)	(5,529)	(6,031)
Recoveries	1,095	1,190	3,296	3,688
Provision	1,221	1,719	2,304	3,844
Ending balance	14,437	14,969	14,437	14,969
Consumer Portfolio Segment [Member] | Consumer Direct [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	3,184	3,164	3,095	3,039
Charge-offs	(456)	(465)	(1,436)	(1,324)
Recoveries	167	223	567	612
Provision	383	299	1,052	894
Ending balance	3,278	3,221	3,278	3,221
Consumer Portfolio Segment [Member] | Home Equity [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	2,103	2,015	2,144	2,107
Charge-offs	(45)	(221)	(223)	(325)
Recoveries	32	15	68	31
Provision	(8)	225	93	221
Ending balance	2,082	2,034	2,082	2,034
Unallocated Financing Receivables [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	991	1,070	1,000	1,100
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(53)	(159)	(62)	(189)
Ending balance	$ 938	$ 911	$ 938	$ 911

GOODWILL AND IDENTIFIABLE INT_3

GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Identifiable Intangible Assets [Abstract]
Gross carrying amount	$ 155,741	$ 150,518
Accumulated amortization	(88,666)	(76,672)
Net carrying amount	67,075	73,846
Estimated aggregate amortization expense for each of five succeeding fiscal years [Abstract]
Oct - Dec 2019	3,962
2020	13,801
2021	11,786
2022	10,105
2023	8,457
Thereafter	18,964
Net carrying amount	67,075	73,846
Components of goodwill [Abstract]
Goodwill, beginning of period	738,327
Goodwill, activity	40,107
Goodwill, end of period	778,434
Accumulated impairment, beginning of period	(4,824)
Accumulated impairment, activity	0
Accumulated impairment, end of period	(4,824)
Goodwill, net, beginning of period	733,503
Goodwill, net, activity	40,107
Goodwill, net, end of period	773,610
Core Deposit Intangibles [Member]
Identifiable Intangible Assets [Abstract]
Gross carrying amount	66,475	62,902
Accumulated amortization	(48,603)	(44,306)
Net carrying amount	17,872	18,596
Estimated aggregate amortization expense for each of five succeeding fiscal years [Abstract]
Net carrying amount	17,872	18,596
Other Intangibles [Member]
Identifiable Intangible Assets [Abstract]
Gross carrying amount	89,266	87,616
Accumulated amortization	(40,063)	(32,366)
Net carrying amount	49,203	55,250
Estimated aggregate amortization expense for each of five succeeding fiscal years [Abstract]
Net carrying amount	$ 49,203	$ 55,250

LEASES (Details)

LEASES (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019USD ($)		Sep. 30, 2019USD ($)
Operating Leases [Abstract]
Term of option to terminate			1 year
Components of Lease Expense [Abstract]
Operating lease cost	$ 2,231		$ 6,493
Variable lease cost	9		9
Short-term lease cost	77	[1]	180	[1]
Total lease cost	2,317		6,682
Cash paid for amounts included in the measurement of lease liabilities [Abstract]
Operating cash outflows for operating leases			5,987
Right-of-use assets obtained in exchange for lease obligations [Abstract]
Operating leases			13,766
Operating leases [Abstract]
Operating lease right-of-use assets	41,948		41,948
Operating lease liabilities	$ 42,769		$ 42,769
Weighted average remaining lease term [Abstract]
Operating leases	6 years 8 months 12 days		6 years 8 months 12 days
Weighted average discount rate [Abstract]
Operating leases	2.95%		2.95%
Maturities of Lease Liabilities [Abstract]
Oct - Dec 2019	$ 2,253		$ 2,253
2020	9,372		9,372
2021	7,934		7,934
2022	6,645		6,645
2023	5,674		5,674
Thereafter	15,697		15,697
Total lease payments	47,575		47,575
Less imputed interest	(4,806)		(4,806)
Total	$ 42,769		$ 42,769
Minimum [Member]
Operating Leases [Abstract]
Remaining term of lease			1 year
Term of option to extend	1 year		1 year
Maximum [Member]
Operating Leases [Abstract]
Remaining term of lease			15 years
Term of option to extend	40 years		40 years
706 North Clinton, LLC [Member]
Operating leases [Abstract]
Operating lease right-of-use assets	$ 5,000		$ 5,000
Operating lease liabilities	$ 5,039		$ 5,039
Weighted average remaining lease term [Abstract]
Operating leases	10 years 2 months 12 days		10 years 2 months 12 days
Weighted average discount rate [Abstract]
Operating leases	3.67%		3.67%
Maturities of Lease Liabilities [Abstract]
Oct - Dec 2019	$ 148		$ 148
2020	591		591
2021	591		591
2022	591		591
2023	591		591
Thereafter	3,538		3,538
Total lease payments	6,050		6,050
Less imputed interest	(1,011)		(1,011)
Total	$ 5,039		$ 5,039
Membership interest	50.00%		50.00%
[1]	Short-term lease cost includes the cost of leases with terms of twelve months or less, excluding leases with terms of one month or less.

MANDATORILY REDEEMABLE PREFER_3

MANDATORILY REDEEMABLE PREFERRED SECURITIES (Details) $ in Millions	Sep. 16, 2019USD ($)	Sep. 30, 2019USD ($)Trust
Mandatorily Redeemable Preferred Securities [Abstract]
Number of unconsolidated subsidiary business trusts owned | Trust		1
Business Trust [Member]
Mandatorily Redeemable Preferred Securities [Abstract]
Percent ownership of unconsolidated subsidiary trusts		100.00%
MBVT Statutory Trust I [Member]
Mandatorily Redeemable Preferred Securities [Abstract]
Redemption of debentures and associated preferred securities	$ 20.6
Kinderhook Capital Trust [Member]
Mandatorily Redeemable Preferred Securities [Abstract]
Redemption of debentures and associated preferred securities	$ 2.1
Preferred Debt [Member] | Community Capital Trust IV [Member]
Terms of preferred securities for each trust [Abstract]
Issuance date		Dec. 8, 2006
Par amount		$ 75
Variable interest rate basis		3 month LIBOR
Effective interest rate		3.77%
Maturity date		Dec. 15, 2036
Call price		Par
Preferred Debt [Member] | Community Capital Trust IV [Member] | LIBOR [Member]
Terms of preferred securities for each trust [Abstract]
Term of variable rate		3 months
Variable interest rate, basis spread		1.65%

BENEFIT PLANS (Details)

BENEFIT PLANS (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Pension Benefits [Member]
Net periodic benefit cost [Abstract]
Service cost	$ 1,270		$ 1,154	$ 3,811	$ 3,396
Interest cost	1,566		1,422	4,698	4,251
Expected return on plan assets	(3,578)		(3,705)	(10,733)	(11,115)
Amortization of unrecognized net loss	642		299	1,926	895
Amortization of prior service cost	17		(60)	48	(225)
Net periodic benefit	(83)		(890)	(250)	(2,798)
Pension Benefits [Member] | Nonqualified Plan [Member] | Unfunded Plan [Member]
Pension Plans [Abstract]
Contribution made to defined benefit pension plan by employer		$ 7,300
Unfunded initial projected benefit obligation	800			800
Post-retirement Benefits [Member]
Net periodic benefit cost [Abstract]
Service cost	0		0	0	0
Interest cost	18		18	53	52
Expected return on plan assets	0		0	0	0
Amortization of unrecognized net loss	9		5	28	15
Amortization of prior service cost	(45)		(45)	(134)	(134)
Net periodic benefit	$ (18)		$ (22)	$ (53)	$ (67)

EARNINGS PER SHARE (Details)

EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
EARNINGS PER SHARE [Abstract]
Weighted-average anti-dilutive stock options outstanding (in shares)	500,000	400,000	500,000	400,000
Basic earnings per share [Abstract]
Net income	$ 39,218	$ 43,106	$ 126,179	$ 127,818
Income attributable to unvested stock-based compensation awards	(102)	(191)	(331)	(563)
Income available to common shareholders	$ 39,116	$ 42,915	$ 125,848	$ 127,255
Weighted-average common shares outstanding - basic (in shares)	51,750,000	51,250,000	51,644,000	51,108,000
Basic earnings per share (in dollars per share)	$ 0.76	$ 0.84	$ 2.44	$ 2.49
Diluted earnings per share [Abstract]
Net income	$ 39,218	$ 43,106	$ 126,179	$ 127,818
Income attributable to unvested stock-based compensation awards	(102)	(191)	(331)	(563)
Income available to common shareholders	$ 39,116	$ 42,915	$ 125,848	$ 127,255
Weighted-average common shares outstanding - basic (in shares)	51,750,000	51,250,000	51,644,000	51,108,000
Assumed exercise of stock options (in shares)	496,000	608,000	522,000	590,000
Weighted-average common shares outstanding - diluted (in shares)	52,246,000	51,858,000	52,166,000	51,698,000
Diluted earnings per share (in dollars per share)	$ 0.75	$ 0.83	$ 2.41	$ 2.46
Stock Repurchase Program [Abstract]
Number of common shares authorized to be repurchased (in shares)					2,500,000	2,500,000
Number of common shares repurchased (in shares)			0	0

COMMITMENTS, CONTINGENT LIABI_3

COMMITMENTS, CONTINGENT LIABILITIES AND RESTRICTIONS (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Commitments, Contingent Liabilities and Restrictions [Abstract]
Contract amount of commitments and contingencies	$ 1,103,095	$ 1,167,745
Minimum [Member]
Commitments, Contingent Liabilities and Restrictions [Abstract]
Range of reasonably possible losses for such matters in the aggregate, beyond the existing recorded liability	0
Maximum [Member]
Commitments, Contingent Liabilities and Restrictions [Abstract]
Range of reasonably possible losses for such matters in the aggregate, beyond the existing recorded liability	1,000
Commitments to Extend Credit [Member]
Commitments, Contingent Liabilities and Restrictions [Abstract]
Contract amount of commitments and contingencies	1,065,127	1,134,576
Standby Letters of Credit [Member]
Commitments, Contingent Liabilities and Restrictions [Abstract]
Contract amount of commitments and contingencies	$ 37,968	$ 33,169

FAIR VALUE, Financial Assets an

FAIR VALUE, Financial Assets and Liabilities Accounted for at Fair Value On a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	$ 2,437,102
Equity securities	461	$ 432
U.S. Treasury and Agency Securities [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	1,506,647	2,023,753
Obligations of State and Political Subdivisions [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	458,090	459,154
Government Agency Mortgage-Backed Securities [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	411,816	382,477
Corporate Debt Securities [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	2,540	2,546
Government Agency Collateralized Mortgage Obligations [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	58,009	68,119
Recurring [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	2,437,102	2,936,049
Equity securities	461	432
Mortgage loans held for sale		83
Total	2,437,910	2,936,615
Recurring [Member] | Interest Rate Swap Agreements [Member]
Available-for-sale investment securities [Abstract]
Derivative asset	1,095	793
Derivative liability	(748)	(742)
Recurring [Member] | U.S. Treasury and Agency Securities [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	1,506,647	2,023,753
Recurring [Member] | Obligations of State and Political Subdivisions [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	458,090	459,154
Recurring [Member] | Government Agency Mortgage-Backed Securities [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	411,816	382,477
Recurring [Member] | Corporate Debt Securities [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	2,540	2,546
Recurring [Member] | Government Agency Collateralized Mortgage Obligations [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	58,009	68,119
Recurring [Member] | Level 1 [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	1,343,370	1,896,931
Equity securities	461	432
Mortgage loans held for sale		0
Total	1,343,831	1,897,363
Recurring [Member] | Level 1 [Member] | Interest Rate Swap Agreements [Member]
Available-for-sale investment securities [Abstract]
Derivative asset	0	0
Derivative liability	0	0
Recurring [Member] | Level 1 [Member] | U.S. Treasury and Agency Securities [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	1,343,370	1,896,931
Recurring [Member] | Level 1 [Member] | Obligations of State and Political Subdivisions [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	0	0
Recurring [Member] | Level 1 [Member] | Government Agency Mortgage-Backed Securities [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	0	0
Recurring [Member] | Level 1 [Member] | Corporate Debt Securities [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	0	0
Recurring [Member] | Level 1 [Member] | Government Agency Collateralized Mortgage Obligations [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	0	0
Recurring [Member] | Level 2 [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	1,093,732	1,039,118
Equity securities	0	0
Mortgage loans held for sale		83
Total	1,094,079	1,039,252
Mortgage loans held for sale, at principal value	0	100
Recurring [Member] | Level 2 [Member] | Interest Rate Swap Agreements [Member]
Available-for-sale investment securities [Abstract]
Derivative asset	1,095	793
Derivative liability	(748)	(742)
Recurring [Member] | Level 2 [Member] | U.S. Treasury and Agency Securities [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	163,277	126,822
Recurring [Member] | Level 2 [Member] | Obligations of State and Political Subdivisions [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	458,090	459,154
Recurring [Member] | Level 2 [Member] | Government Agency Mortgage-Backed Securities [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	411,816	382,477
Recurring [Member] | Level 2 [Member] | Corporate Debt Securities [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	2,540	2,546
Recurring [Member] | Level 2 [Member] | Government Agency Collateralized Mortgage Obligations [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	58,009	68,119
Recurring [Member] | Level 3 [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	0	0
Equity securities	0	0
Mortgage loans held for sale		0
Total	0	0
Recurring [Member] | Level 3 [Member] | Interest Rate Swap Agreements [Member]
Available-for-sale investment securities [Abstract]
Derivative asset	0	0
Derivative liability	0	0
Recurring [Member] | Level 3 [Member] | U.S. Treasury and Agency Securities [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	0	0
Recurring [Member] | Level 3 [Member] | Obligations of State and Political Subdivisions [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	0	0
Recurring [Member] | Level 3 [Member] | Government Agency Mortgage-Backed Securities [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	0	0
Recurring [Member] | Level 3 [Member] | Corporate Debt Securities [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	0	0
Recurring [Member] | Level 3 [Member] | Government Agency Collateralized Mortgage Obligations [Member]
Available-for-sale investment securities [Abstract]
Available-for-sale investment securities	$ 0	$ 0

FAIR VALUE, Assets and Liabilit

FAIR VALUE, Assets and Liabilities Measured on Nonrecurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Assets and Liabilities Measured on Nonrecurring Basis [Abstract]
Impaired loans	$ 1,729	$ 1,102
Mortgage servicing rights	93
Other real estate owned	1,258	1,320
Valuation allowance	0	956
Mortgage Servicing Rights [Member]
Assets and Liabilities Measured on Nonrecurring Basis [Abstract]
Valuation allowance	300	0
Non-recurring [Member]
Assets and Liabilities Measured on Nonrecurring Basis [Abstract]
Impaired loans	1,729	1,102
Mortgage servicing rights	93	0
Other real estate owned	1,258	1,320
Total	3,080	2,422
Non-recurring [Member] | Level 1 [Member]
Assets and Liabilities Measured on Nonrecurring Basis [Abstract]
Impaired loans	0	0
Mortgage servicing rights	0	0
Other real estate owned	0	0
Total	0	0
Non-recurring [Member] | Level 2 [Member]
Assets and Liabilities Measured on Nonrecurring Basis [Abstract]
Impaired loans	0	0
Mortgage servicing rights	0	0
Other real estate owned	0	0
Total	0	0
Non-recurring [Member] | Level 3 [Member]
Assets and Liabilities Measured on Nonrecurring Basis [Abstract]
Impaired loans	1,729	1,102
Mortgage servicing rights	93	0
Other real estate owned	1,258	1,320
Total	$ 3,080	$ 2,422

FAIR VALUE, Significant Unobser

FAIR VALUE, Significant Unobservable Inputs (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2019USD ($)	Dec. 31, 2018USD ($)
Significant Unobservable Inputs used in determination of Fair Value of Assets Classified as Level 3 [Abstract]
Impaired loans	$ 1,729	$ 1,102
Other real estate owned	$ 1,258	$ 1,320
Other real estate owned, Valuation Technique [Extensible List]	us-gaap:MarketApproachValuationTechniqueMember	us-gaap:MarketApproachValuationTechniqueMember
Other real estate owned, Measurement Input [Extensible List]	us-gaap:MeasurementInputCostToSellMember	us-gaap:MeasurementInputCostToSellMember
Mortgage servicing rights	$ 93
Discounted Cash Flow [Member] | Weighted Average Constant Prepayment Rate [Member]
Significant Unobservable Inputs used in determination of Fair Value of Assets Classified as Level 3 [Abstract]
Mortgage servicing rights, measurement input	0.430
Discounted Cash Flow [Member] | Weighted Average Discount Rate [Member]
Significant Unobservable Inputs used in determination of Fair Value of Assets Classified as Level 3 [Abstract]
Mortgage servicing rights, measurement input	0.0269
Discounted Cash Flow [Member] | Adequate Compensation [Member]
Significant Unobservable Inputs used in determination of Fair Value of Assets Classified as Level 3 [Abstract]
Mortgage servicing rights, measurement input	7
Minimum [Member] | Fair Value of Collateral [Member] | Estimated Cost of Disposal/Market Adjustment [Member]
Significant Unobservable Inputs used in determination of Fair Value of Assets Classified as Level 3 [Abstract]
Impaired loans, measurement input	0.090	0.090
Other real estate owned, measurement input	0.005	0.090
Maximum [Member] | Fair Value of Collateral [Member] | Estimated Cost of Disposal/Market Adjustment [Member]
Significant Unobservable Inputs used in determination of Fair Value of Assets Classified as Level 3 [Abstract]
Impaired loans, measurement input	0.404	0.354
Other real estate owned, measurement input	0.774	0.693
Weighted Average [Member] | Fair Value of Collateral [Member] | Estimated Cost of Disposal/Market Adjustment [Member]
Significant Unobservable Inputs used in determination of Fair Value of Assets Classified as Level 3 [Abstract]
Impaired loans, measurement input	0.404	0.288
Other real estate owned, measurement input	0.357	0.238

FAIR VALUE, Carrying Amounts an

FAIR VALUE, Carrying Amounts and Estimated Fair Values of Other Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Carrying Value [Member]
Financial assets [Abstract]
Net loans	$ 6,803,768	$ 6,231,837
Financial liabilities [Abstract]
Deposits	9,168,285	8,322,371
Short-term borrowings	0	54,400
Securities sold under agreement to repurchase, short-term	233,333	259,367
Other long-term debt	4,328	1,976
Subordinated notes payable	13,814	0
Subordinated debt held by unconsolidated subsidiary trusts	77,320	97,939
Fair Value [Member]
Financial assets [Abstract]
Net loans	6,971,242	6,247,939
Financial liabilities [Abstract]
Deposits	9,166,701	8,308,765
Short-term borrowings	0	54,400
Securities sold under agreement to repurchase, short-term	233,333	259,367
Other long-term debt	4,303	1,921
Subordinated notes payable	13,814	0
Subordinated debt held by unconsolidated subsidiary trusts	$ 77,320	$ 97,939

DERIVATIVE INSTRUMENTS (Details

DERIVATIVE INSTRUMENTS (Details) - Interest Rate Swap [Member] - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Derivative Instruments [Abstract]
Derivative, notional amount	$ 16.8	$ 37
Derivative weighted average receive rate	4.01%	4.34%
Derivative weighted average pay rate	4.38%	3.84%
Weighted average maturity period	6 years 4 months 24 days	5 years 6 months
Designated as Hedging Instrument [Member] | Fair Value Hedging [Member]
Derivative Instruments [Abstract]
Derivative, notional amount	$ 6.2	$ 6.6
Derivative weighted average receive rate	2.65%	2.92%
Derivative weighted average pay rate	3.11%	3.11%
Weighted average maturity period	13 years 9 months 18 days	14 years 6 months

DERIVATIVE INSTRUMENTS, Cumulat

DERIVATIVE INSTRUMENTS, Cumulative Basis Adjustments for Fair Value Hedges (Details) - Loans [Member] $ in Thousands	Sep. 30, 2019USD ($)
Cumulative Basis Adjustments for Fair Value Hedges [Abstract]
Carrying amount of the hedged assets	$ 6,307
Cumulative amount of fair value hedging adjustment included in the carrying amount of the hedged assets	$ (347)

DERIVATIVE INSTRUMENTS, Fair Va

DERIVATIVE INSTRUMENTS, Fair Values of Derivative Instruments (Details) $ in Thousands	Sep. 30, 2019USD ($)
Fair Values of Derivative Instruments [Abstract]
Derivative assets	$ 1,095
Derivative liabilities	748
Interest Rate Swap [Member] | Designated as Hedging Instrument [Member] | Other Assets [Member]
Fair Values of Derivative Instruments [Abstract]
Derivative assets	347
Interest Rate Swap [Member] | Not Designated as Hedging Instrument [Member] | Other Assets [Member]
Fair Values of Derivative Instruments [Abstract]
Derivative assets	748
Interest Rate Swap [Member] | Not Designated as Hedging Instrument [Member] | Accrued Interest and Other Liabilities [Member]
Fair Values of Derivative Instruments [Abstract]
Derivative liabilities	$ 748

SEGMENT INFORMATION (Details)

SEGMENT INFORMATION (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jul. 12, 2019	Dec. 31, 2018
Information about reportable segments [Abstract]
Net interest income	$ 91,276	$ 86,198	$ 266,435	$ 257,668
Provision for loan losses	1,751	2,215	5,573	8,342
Noninterest revenues	57,094	55,791	173,496	169,841
Amortization of intangible assets	3,960	4,427	11,994	13,780
Acquisition expenses	6,061	(832)	7,789	(769)
Other operating expenses	86,908	81,638	256,974	244,665
Income before income taxes	49,690	54,541	157,601	161,491
Assets	11,597,297	10,659,567	11,597,297	10,659,567		$ 10,607,295
Goodwill	773,610	733,479	773,610	733,479	$ 40,107	$ 733,503
Core deposit intangibles & Other intangibles	67,075	78,221	67,075	78,221
Eliminations [Member]
Information about reportable segments [Abstract]
Net interest income	0	0	0	0
Provision for loan losses	0	0	0	0
Noninterest revenues	(669)	(763)	(2,231)	(2,159)
Amortization of intangible assets	0	0	0	0
Acquisition expenses	0	0	0	0
Other operating expenses	(669)	(763)	(2,231)	(2,159)
Income before income taxes	0	0	0	0
Assets	(76,505)	(53,200)	(76,505)	(53,200)
Goodwill	0	0	0	0
Core deposit intangibles & Other intangibles	0	0	0	0
Banking [Member] | Operating Segments [Member]
Information about reportable segments [Abstract]
Net interest income	91,018	86,060	265,860	257,313
Provision for loan losses	1,751	2,215	5,573	8,342
Noninterest revenues	17,790	18,002	57,059	58,399
Amortization of intangible assets	1,439	1,535	4,297	4,914
Acquisition expenses	6,061	(832)	7,789	(782)
Other operating expenses	61,839	57,863	182,186	172,283
Income before income taxes	37,718	43,281	123,074	130,955
Assets	11,398,191	10,440,732	11,398,191	10,440,732
Goodwill	670,023	629,916	670,023	629,916
Core deposit intangibles & Other intangibles	17,872	20,111	17,872	20,111
Employee Benefit Services [Member] | Operating Segments [Member]
Information about reportable segments [Abstract]
Net interest income	209	102	448	264
Provision for loan losses	0	0	0	0
Noninterest revenues	24,830	23,815	73,919	70,316
Amortization of intangible assets	1,667	1,970	5,105	6,047
Acquisition expenses	0	0	0	7
Other operating expenses	14,721	14,025	43,985	41,938
Income before income taxes	8,651	7,922	25,277	22,588
Assets	201,442	205,565	201,442	205,565
Goodwill	83,275	83,275	83,275	83,275
Core deposit intangibles & Other intangibles	39,440	46,514	39,440	46,514
All Other [Member] | Operating Segments [Member]
Information about reportable segments [Abstract]
Net interest income	49	36	127	91
Provision for loan losses	0	0	0	0
Noninterest revenues	15,143	14,737	44,749	43,285
Amortization of intangible assets	854	922	2,592	2,819
Acquisition expenses	0	0	0	6
Other operating expenses	11,017	10,513	33,034	32,603
Income before income taxes	3,321	3,338	9,250	7,948
Assets	74,169	66,470	74,169	66,470
Goodwill	20,312	20,288	20,312	20,288
Core deposit intangibles & Other intangibles	$ 9,763	$ 11,596	$ 9,763	$ 11,596