Independent Bank (INDB) 10-K 27 Feb 20 2019 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2019	Feb. 25, 2020
Entity Information [Line Items]
Document Annual Report	true
Entity File Number	1-9047
Entity Address, Address Line One	2036 Washington Street,
Document Transition Report	false
Entity Incorporation, State or Country Code	MA
Entity Registrant Name	Independent Bank Corp
City Area Code	(781)
Local Phone Number	878-6100
Entity Central Index Key	0000776901
Document Type	10-K
Document Period End Date	Dec. 31, 2019
Amendment Flag	false
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	Yes
Entity Public Float	$ 2,575,396,930
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Common Stock, Shares Outstanding		34,326,507
Entity Address, City or Town	Hanover,
Entity Tax Identification Number	04-2870273
Entity Shell Company	false
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02339
Documents Incorporated by Reference [Text Block]	E
Mailing Address [Member]
Entity Information [Line Items]
Entity Address, Address Line One	288 Union Street,
Entity Address, City or Town	Rockland,
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02370
NASDAQ/NGS (GLOBAL SELECT MARKET) [Member]
Entity Information [Line Items]
Title of 12(b) Security	Common Stock, $0.01 par value per share
Trading Symbol	INDB
Security Exchange Name	NASDAQ

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Assets
Cash and due from banks	$ 114,686	$ 127,503
Interest-earning deposits with banks	36,288	122,952
Securities
Debt Securities, Trading, and Equity Securities, FV-NI	2,179	1,504
Equity Securities, FV-NI	21,261	19,477
Debt Securities, Available-for-sale	426,424	442,752
Held to maturity (fair value $753,263 and $603,640)	740,806	611,490
Total securities	1,190,670	1,075,223
Loans Receivable Held-for-sale, Net, Not Part of Disposal Group	33,307	6,431
Loans
Total loans	8,873,639	6,906,194
Less: allowance for loan losses	(67,740)	(64,293)
Net loans	8,805,899	6,841,901
Federal Home Loan Bank stock	14,424	15,683
Bank premises and equipment, net	123,674	97,581
Goodwill	506,206	256,105
Other intangible assets	29,286	15,250
Cash surrender value of life insurance policies	197,372	160,456
Other assets	343,353	132,507
Total assets	11,395,165	8,851,592
Deposits
Noninterest-bearing demand deposits	2,662,591	2,450,907
Savings and interest checking accounts	3,232,909	2,865,349
Money market	1,856,552	1,399,761
Time certificates of deposit of $100,000 and over	663,645	351,629
Other time certificates of deposits	731,670	359,474
Total deposits	9,147,367	7,427,120
Borrowings
Advances from Federal Home Loan Banks	115,748	147,806
Long-term Debt	74,906	0
Junior subordinated debentures (less unamortized debt issuance costs of $40 and $118)	62,848	76,173
Subordinated debentures (less unamortized debt issuance costs of $399 and $272)	49,601	34,728
Total borrowings	303,103	258,707
Other liabilities	236,552	92,275
Total liabilities	9,687,022	7,778,102
Commitments and contingencies	0	0
Stockholders' Equity
Preferred stock, $.01 par value; authorized: 1,000,000 shares, outstanding: none	0	0
Common stock, $.01 par value; authorized: 75,000,000 shares, issued and outstanding: 34,377,388 shares at December 31, 2019 and 28,080,408 shares at December 31, 2018 (includes 147,184 and 153,459 shares of unvested participating restricted stock awards, respectively)	342	279
Value of shares held in rabbi trust at cost: 143,820 shares at December 31, 2019 and 153,226 shares at December 31, 2018	(4,735)	(4,718)
Compensation and Benefits Trust	4,735	4,718
Additional paid in capital	1,035,450	527,648
Retained earnings	654,182	546,736
Accumulated other comprehensive loss, net of tax	18,169	(1,173)
Total stockholders' equity	1,708,143	1,073,490
Liabilities and Equity	11,395,165	8,851,592
Commercial And Industrial [Member]
Loans
Financing Receivable, before Allowance for Credit Loss	1,395,036	1,093,629
Total loans	1,395,036	1,093,629
Less: allowance for loan losses	(17,594)	(15,760)
Commercial Real Estate [Member]
Loans
Financing Receivable, before Allowance for Credit Loss	4,002,359	3,251,248
Total loans	4,002,359	3,251,248
Less: allowance for loan losses	(32,935)	(32,370)
Construction Loans [Member]
Loans
Financing Receivable, before Allowance for Credit Loss	547,293	365,165
Total loans	547,293	365,165
Less: allowance for loan losses	(6,053)	(5,158)
Small Business [Member]
Loans
Financing Receivable, before Allowance for Credit Loss	174,497	164,676
Total loans	174,497	164,676
Less: allowance for loan losses	(1,746)	(1,756)
Residential Real Estate [Member]
Loans
Financing Receivable, before Allowance for Credit Loss	1,590,569	923,294
Total loans	1,590,569	923,294
Less: allowance for loan losses	(3,440)	(3,219)
Home Equity 1st Position [Member]
Loans
Financing Receivable, before Allowance for Credit Loss	649,255	654,083
Home Equity Subordinate Position [Member]
Loans
Financing Receivable, before Allowance for Credit Loss	484,543	438,001
Consumer Portfolio Segment [Member]
Loans
Financing Receivable, before Allowance for Credit Loss	30,087	16,098
Total loans	30,087	16,098
Less: allowance for loan losses	$ (396)	$ (422)

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Time certificates of deposit least amount	$ 100,000	$ 100,000
Securities held to maturity, fair value	$ 753,263,000	$ 603,640,000
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	75,000,000	75,000,000
Common stock, shares issued	34,377,388	28,080,408
Common stock, unvested restricted Stock awards	147,184	153,459
Shares held in rabbit trust at cost	143,820	153,226
Common Stock Outstanding
Common stock, shares outstanding	34,377,388	28,080,408
Junior Subordinated Debt [Member]
Unamortized Debt Issuance Expense	$ 40,000	$ 118,000
Subordinated Debt [Member]
Unamortized Debt Issuance Expense	399,000	272,000
Long-term Debt [Member]
Unamortized Debt Issuance Expense	$ 94,000	$ 0

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Interest income
Interest and fees on loans	$ 411,460	$ 294,293	$ 253,131
Interest Income, Securities, Operating, Taxable	32,405	26,513	22,465
Nontaxable interest and dividends on securities	51	60	88
Interest on loans held for sale	891	159	92
Interest on federal funds sold and short-term investments	2,207	2,676	1,418
Total interest and dividend income	447,014	323,701	277,194
Interest expense
Interest on deposits	41,186	19,995	12,702
Interest on borrowings	12,693	5,541	5,632
Total interest expense	53,879	25,536	18,334
Net interest income	393,135	298,165	258,860
Provision (benefit)	6,000	4,775	2,950
Net interest income after provision for loan losses	387,135	293,390	255,910
Noninterest income
Deposit account fees	20,040	18,327	17,822
Interchange and ATM fees	22,152	18,916	17,291
Investment Banking, Advisory, Brokerage, and Underwriting Fees and Commissions	28,719	26,155	23,802
Fees and Commission Mortgage Banking	11,454	4,071	4,960
Increase in cash surrender value of life insurance policies	5,013	4,060	4,127
Gain Realized on Life Insurance Policies	434	1,463	0
Loan level derivative income	6,478	2,373	3,836
Other noninterest income	21,004	13,140	11,156
Total noninterest income	115,294	88,505	82,994
Noninterest expenses
Salaries and employee benefits	149,165	124,328	116,600
Occupancy and equipment expenses	33,207	27,098	24,693
Data processing & facilities management	6,516	5,125	4,988
FDIC assessment	1,394	2,774	3,068
Advertising expense	5,444	4,942	4,989
Consulting expense	5,448	3,891	4,038
Cost, Amortization	5,545	2,344	2,711
Debit Card Expense	4,220	3,429	3,430
Available-for-Sale Securities - Fixed Income Gross Realized Losses	1,462	0	0
Merger and acquisition expense	26,433	11,168	3,393
Software Maintenance	5,511	4,202	3,636
Other noninterest expenses	39,976	36,668	32,813
Total noninterest expenses	284,321	225,969	204,359
Income before income taxes	218,108	155,926	134,545
Provision for income taxes	52,933	34,304	47,341
Net Income	$ 165,175	$ 121,622	$ 87,204
Basic earnings per share (in dollars per share)	$ 5.03	$ 4.41	$ 3.19
Diluted earnings per share (in dollars per share)	$ 5.03	$ 4.40	$ 3.19
Weighted average common shares (basic) (in shares)	32,810,433	27,592,380	27,294,028
Common share equivalents (in shares)	45,801	61,428	78,076
Weighted average common shares (diluted) (in shares)	32,856,234	27,653,808	27,372,104
Retained Earnings
Noninterest expenses
Net Income	$ 165,175	$ 121,622	$ 87,204
Cash dividends declared (in dollars per share)	$ 1.76	$ 1.52	$ 1.28

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income		$ 165,175	$ 121,622	$ 87,204
Other comprehensive income (loss), net of tax
Net change in fair value of securities available for sale		10,345	(4,501)	(677)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax		10,331	4,829	443
Net change in other comprehensive income for defined benefit postretirement plans	[1]	(1,334)	1,558	(260)
Total other comprehensive income (loss)		19,342	1,886	(494)
Total comprehensive income		$ 184,517	$ 123,508	$ 86,710
[1]	The amortization of prior service costs is included in the computation of net periodic pension costs as disclosed in Note 15 - Employee Benefit Plans .

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands		Total	Common Stock Outstanding	Common Stock	Value of Shares Held in Rabbi Trust at Cost	Deferred Compensation Obligation	Additional Paid in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Beginning balance at Dec. 31, 2016		$ 864,690		$ 268	$ (4,277)	$ 4,277	$ 451,664	$ 414,095	$ (1,337)
Beginning balance (in shares) at Dec. 31, 2016			27,005,813
Net income		87,204						$ 87,204
Other comprehensive loss		(494)							(494)
Common Stock, Dividends, Per Share, Declared								$ 1.28
Common dividend declared		(34,997)						$ (34,997)
Common stock issued for acquisition		23,468		4			23,464
Common stock issued for acquisition (in shares)			369,286
Proceeds from exercise of stock options, net of cash paid		214					214
Proceeds from exercise of stock options (in shares)			19,340
Stock based compensation		3,333					3,333
Restricted stock awards issued, net of awards surrendered (in shares)			31,665
Restricted stock awards issued, net of awards surrendered		(1,422)		1			(1,423)
Stock Issued During Period, Shares, Other			24,086
Stock Issued During Period, Value, Other		1,636					1,636
Increase (Decrease) in Deferred Compensation					(313)	313
Ending balance (in shares) at Dec. 31, 2017			27,450,190
Ending balance at Dec. 31, 2017		943,809		273	(4,590)	4,590	479,430	465,937	(1,831)
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets	[1]	177					542	(365)
Prior Period Reclassification Adjustment	[2]	0						397	(397)
Net income		121,622						$ 121,622
Other comprehensive loss		1,886							1,886
Common Stock, Dividends, Per Share, Declared								$ 1.52
Common dividend declared		(42,051)						$ (42,051)
Common stock issued for acquisition		42,474		5			42,469
Common stock issued for acquisition (in shares)			528,353
Proceeds from exercise of stock options, net of cash paid		184		0			184
Proceeds from exercise of stock options (in shares)			23,195
Stock based compensation		4,225					4,225
Restricted stock awards issued, net of awards surrendered (in shares)			43,383
Restricted stock awards issued, net of awards surrendered		(1,371)		1			(1,372)
Stock Issued During Period, Shares, Other			35,287
Stock Issued During Period, Value, Other		2,712					2,712
Increase (Decrease) in Deferred Compensation		0
Increase (Decrease) in Deferred Compensation and Other Retirement Benefits					(128)	128
Ending balance (in shares) at Dec. 31, 2018			28,080,408
Ending balance at Dec. 31, 2018		1,073,490		279	(4,718)	4,718	527,648	546,736	(1,173)
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets	[3]	0
Net income		29,934
Ending balance (in shares) at Dec. 31, 2018			28,080,408
Ending balance at Dec. 31, 2018		1,073,490		279	(4,718)	4,718	527,648	546,736	(1,173)
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets	[3]							831	(831)
Net income		165,175						$ 165,175
Other comprehensive loss		19,342							19,342
Common Stock, Dividends, Per Share, Declared								$ 1.76
Common dividend declared		(57,729)						$ (57,729)
Common stock issued for acquisition		499,693		61			499,632
Common stock issued for acquisition (in shares)			6,166,010
Proceeds from exercise of stock options, net of cash paid		281					281
Proceeds from exercise of stock options (in shares)			14,646
Stock based compensation		4,403					4,403
Restricted stock awards issued, net of awards surrendered (in shares)			50,080
Restricted stock awards issued, net of awards surrendered		(1,463)		1			(1,464)
Stock Issued During Period, Shares, Other			66,244
Stock Issued During Period, Value, Other		4,951		1			4,950
Increase (Decrease) in Deferred Compensation		0
Increase (Decrease) in Deferred Compensation and Other Retirement Benefits					(17)	17
Ending balance (in shares) at Dec. 31, 2019			34,377,388
Ending balance at Dec. 31, 2019		$ 1,708,143		$ 342	$ (4,735)	$ 4,735	$ 1,035,450	$ 654,182	$ 18,169
[1]	Represents adjustment needed to reflect the cumulative impact on retained earnings for previously recognized stock based compensation, which included an adjustment for estimated forfeitures. Pursuant to the Company's adoption of Accounting Standards Update 2016-09, the Company has elected to recognize stock based compensation without inclusion of a forfeiture estimate, and as such has recognized this adjustment to present retained earnings consistent with this election.
[2]	Represents adjustment needed to reflect the cumulative impact on retained earnings for reclassification of the income tax effects attributable to accumulated other comprehensive income, as a result of the Tax Cuts and Jobs Act (the "Tax Act"). Pursuant to the Company's adoption of Accounting Standards Update 2018-02, the Company has elected to reclassify amounts stranded in other comprehensive income to retained earnings.
[3]	Represents adjustment needed to reflect the cumulative impact on retained earnings for the classification and measurement of investments in equity securities. Pursuant to the Company's adoption of Accounting Standards Update 2016-01, the Company's investments in equity securities will no longer be classified as available for sale, therefore the Company was required to reclassify the net unrealized gain recognized on the change in fair value of these equity securities from other comprehensive income to retained earnings.

Consolidated Statements of Cash

Consolidated Statements of Cash Flows	12 Months Ended
	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)
Cash flow from operating activities
Net income	$ 165,175,000	$ 121,622,000	$ 87,204,000
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization	19,439,000	15,629,000	15,760,000
Change In Unamortized Net Loan Costs And Premiums	(10,086,000)	365,000	(79,000)
Provision for loan losses	6,000,000	4,775,000	2,950,000
Deferred income tax expense (benefit)	10,594,000	(4,497,000)	9,211,000
Tax Expense related to a change in tax law	0	0	466,000
Equity Securities, FV-NI, Gain (Loss)	(1,566,000)	1,225,000
Loss on write-down of investments in securities available for sale	1,462,000		(3,000)
Net gain on bank premises and equipment	(474,000)	(1,126,000)	(108,000)
Net loss on other real estate owned and foreclosed assets	401,000	112,000	288,000
Realized gain on sale leaseback transaction	(578,000)	(730,000)	(1,034,000)
Stock based compensation	4,403,000	4,225,000	3,333,000
Increase in cash surrender value of life insurance policies	(5,013,000)	(4,060,000)	(4,127,000)
Gain Realized on Life Insurance Policies	(434,000)	(1,463,000)	0
Operating Lease, Payments	(10,669,000)	0	0
Change in Fair Value on Loans Held for Sale	(822,000)	51,000	113,000
Net change in:
Trading assets	(675,000)	(180,000)	(520,000)
Loans held for sale	59,932,000	(1,714,000)	1,258,000
Other assets	(39,850,000)	503,000	20,022,000
Other liabilities	19,283,000	7,100,000	(3,825,000)
Total adjustments	51,347,000	20,215,000	43,705,000
Net cash provided by operating activities	216,522,000	141,837,000	130,909,000
Cash flows provided by (used) in investing activities
Proceeds from Sale of Debt and Equity Securities, FV-NI, Held-for-investment	1,461,000	5,752,000
Increase (Decrease) in Equity Securities, FV-NI	(711,000)	(6,315,000)	0
Proceeds from Sale of Available-for-sale Securities, Equity			0
Proceeds from Sale of Debt Securities, Available-for-sale	45,863,000		1,027,000
Proceeds from maturities and principal repayments of securities available for sale	51,104,000	82,418,000	54,191,000
Payments to Acquire Debt Securities, Available-for-sale	(68,677,000)	(78,990,000)	(140,885,000)
Proceeds from maturities and principal repayments of securities held to maturity	126,991,000	82,355,000	78,757,000
Purchases of securities held to maturity	(59,967,000)	(195,538,000)	(89,033,000)
Net redemption (purchases) of Federal Home Loan Bank stock	18,896,000	(2,376,000)	386,000
Investments in low income housing projects	(10,052,000)	(3,434,000)	(7,645,000)
Purchases of life insurance policies	(163,000)	(164,000)	(164,000)
Proceeds from Life Insurance Policy	3,162,000	2,850,000	0
Net (increase) decrease in loans	27,816,000	(258,633,000)	(204,702,000)
Cash Acquired in Excess of Payments to Acquire Business			6,289,000
Net cash acquired (paid) in business combinations	(105,264,000)	(6,906,000)
Purchases of bank premises and equipment	(16,583,000)	(11,106,000)	(25,080,000)
Proceeds from the sale of bank premises and equipment	3,796,000	2,189,000	6,306,000
Proceeds from the sale of other real estate owned and foreclosed assets	2,488,000	387,000	3,784,000
Net cash provided by (used in) investing activities	20,160,000	(387,511,000)	(316,769,000)
Cash flows provided by (used in) financing activities
Net decrease in time deposits	(45,272,000)	(1,430,000)	(19,509,000)
Net increase (decrease) in other deposits	(160,637,000)	280,017,000	177,241,000
Net proceeds from (repayments of) short-term Federal Home Loan Bank borrowings	(132,046,000)	67,046,000
Repayments of long-term Federal Home Loan Bank borrowings	(25,000,000)	(2,475,000)	0
Net decrease in customer repurchase agreements		(21,503,000)	(14,234,000)
Proceeds from Lines of Credit	49,980,000	0	0
Repayments of Lines of Credit	(49,980,000)	0	0
Proceeds from Debt, Net of Issuance Costs	74,867,000	0	0
RepaymentsOfJuniorSubordinatedDebt	(13,329,000)	0	0
Proceeds from Issuance of Subordinated Long-term Debt	49,526,000	0	0
Repayments of Subordinated Debt	(34,767,000)	0	0
Net proceeds from exercise of stock options	281,000	184,000	214,000
Restricted stock awards issued, net of awards surrendered	(1,463,000)	(1,371,000)	(1,422,000)
Proceeds from shares issued under the direct stock purchase plan	4,951,000	2,712,000	1,636,000
Common dividends paid	(53,274,000)	(40,167,000)	(34,045,000)
Net cash provided by (used in) financing activities	(336,163,000)	283,013,000	109,881,000
Net increase (decrease) in cash and cash equivalents	(99,481,000)	37,339,000	(75,979,000)
Cash and cash equivalents at beginning of year	250,455,000	213,116,000	289,095,000
Cash and cash equivalents at end of period	150,974,000	250,455,000	213,116,000
Supplemental schedule of noncash investing and financing activities
Interest Paid, Excluding Capitalized Interest, Operating Activities	49,704,000	25,337,000	18,626,000
Income taxes	39,575,000	27,809,000	32,865,000
Transfer of loans to other real estate owned and foreclosed assets			511,000
Capital commitment relating to Low Income Housing Project investments, noncash	36,543,000	2,833,000	20,000
Transfer of customer repurchase agreements to deposits noncash	0	141,176,000	0
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	14,951,000	0	0
Operating Lease, Right-of-Use Asset	56,600,000
Operating Lease, Liability	58,302,000	0
Deferred Rent Credit		1,300,000
In conjunction with the Company's acquisitions, assets were acquired and liabilities were assumed as follows
Common stock issued for acquisition	$ 499,693,000	42,474,000	23,468,000
Fair value of assets acquired, net of cash acquired		362,286,000	179,252,000
Fair value of liabilities assumed		$ 312,906,000	$ 162,073,000

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Significant Accounting Policies [Text Block]	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Nature of Operations Independent Bank Corp. (the "Company") is a bank holding company whose principal subsidiary is Rockland Trust Company ("Rockland Trust" or the "Bank"). Rockland Trust is a state-chartered commercial bank, which operates ninety-five full service and two limited service retail branches, fifteen commercial banking centers, nine investment management offices and seven mortgage lending centers located in Eastern Massachusetts, Greater Boston, the South Shore, the Cape and Islands, as well as in Worcester County and Rhode Island. Rockland Trust deposits are insured by the Federal Deposit Insurance Corporation, subject to regulatory limits. The Company’s primary source of income is from providing loans to individuals and small-to-medium sized businesses in its market area. Rockland Trust is a community-oriented commercial bank, and the community banking business is the Company's only reportable operating segment. Principles of Consolidation The consolidated financial statements include the accounts of the Company, the Bank and other wholly-owned subsidiaries, except subsidiaries that are not deemed necessary to be consolidated. All significant intercompany balances and transactions have been eliminated in consolidation. The Company determines whether it has a controlling financial interest in an entity by first evaluating whether the entity is a voting interest entity or a variable interest entity under GAAP. Voting interest entities are entities in which the total equity investment at risk is sufficient to enable the entity to finance itself independently and provides the equity holders with the obligation to absorb losses, the right to receive residual returns and the right to make decisions about the entity’s activities. The Company would consolidate voting interest entities in which it has all, or at least a majority of, the voting interest. As defined in applicable accounting standards, variable interest entities ("VIEs") are entities that lack one or more of the characteristics of a voting interest entity. A controlling financial interest in a VIE is present when the Company has both the power and ability to direct the activities of the VIE that most significantly impact the VIE's economic performance and an obligation to absorb losses or the right to receive benefits that could potentially be significant to the VIE. The Company also owns the common stock of various trusts which have issued trust preferred securities. These trusts are VIEs in which the Company is not the primary beneficiary and, therefore, are not consolidated. The trust's only assets are junior subordinated debentures issued by the Company, which were acquired by the trust using the proceeds from the issuance of the trust preferred securities and common stock. The junior subordinated debentures are included in long-term debt and the Company’s equity interest in the trust is included in other assets in the accompanying Consolidated Balance Sheets. Interest expense on the junior subordinated debentures is reported in interest expense on long-term debt in the accompanying Consolidated Statements of Income. Reclassification Certain previously reported amounts have been reclassified to conform to the current year’s presentation. Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America ("GAAP") requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting periods. Actual results could vary from these estimates. Material estimates that are particularly susceptible to significant changes in the near-term relate to the determination of the allowance for loan losses, income taxes, valuation and potential impairment of investment securities, other-than-temporary impairment ("OTTI") of certain investment securities, as well as valuation of goodwill and other intangibles and their respective analyses of impairment. Significant Concentrations of Credit Risk The vast majority of the Bank’s lending activities are conducted in Massachusetts and Rhode Island. The Bank originates commercial and industrial loans, commercial and residential real estate loans, including construction loans, small business loans, home equity loans, and other consumer loans for its portfolio. The Bank considers a concentration of credit to a particular industry to exist when the aggregate credit exposure which includes direct, indirect or contingent obligations to a borrower, an affiliated group of borrowers or a nonaffiliated group of borrowers engaged in one industry, exceeds 10% of the Bank’s loan portfolio. Loans originated by the Bank to lessors of nonresidential buildings represented 17.5% and 15.1% of the total loan portfolio at December 31, 2019 and 2018 , respectively. Within this concentration category, the Company believes it is well diversified among collateral property types and tenant industries. Cash and Cash Equivalents For purposes of reporting cash flows, cash and cash equivalents may include cash on hand, amounts due from banks, inclusive of interest-earning deposits held at banks, and federal funds sold. Generally, federal funds are sold for up to two week periods. Securities Investment securities are classified at the time of purchase as available for sale, held to maturity, trading, or equity. Classification is constantly re-evaluated for consistency with corporate goals and objectives. Trading and equity securities are recorded at fair value with subsequent changes in fair value recorded in earnings. Debt securities that management has the positive intent and ability to hold to maturity are classified as held to maturity and recorded at amortized cost. Debt securities not classified as held to maturity or trading are classified as available for sale and recorded at fair value, with changes in fair value excluded from earnings and reported in other comprehensive income, net of related tax. Purchase premiums and discounts are recognized in interest income, using the interest method, to arrive at periodic interest income at a constant effective yield, thereby reflecting the securities market yield. Gains and losses on the sale of securities are recorded on the trade date and are determined using the specific identification method. Declines in the fair value of held to maturity and available for sale securities below their amortized cost deemed to be OTTI are written down to fair value as determined by a cash flow analysis. To the extent the estimated cash flows do not support the amortized cost, the deficiency is considered to be due to credit loss and recognized in earnings. Unless the Company intends to sell the security, or if it is more likely than not that the Company will be required to sell the debt security before its anticipated recovery, the remainder of the OTTI charge is considered to be due to other factors, such as liquidity or interest rates, and thus is not recognized in earnings, but rather through other comprehensive income, net of related tax. The Company evaluates individual securities that have fair values below cost for six months or longer, or for a shorter period of time if considered appropriate by management, to determine if the decline in fair value is other-than-temporary. Consideration is given to the obligor of the security, whether the security is guaranteed, whether there is a projected adverse change in cash flows, the liquidity of the security, the type of security, the capital position of security issuers, and payment history of the security, amongst other factors when evaluating such securities. Loans Held for Sale The Bank primarily classifies new residential real estate mortgage loans as held for sale based on intent, which is determined when loans are underwritten. Residential real estate mortgage loans not designated as held for sale are retained based upon available liquidity, for interest rate risk management and other business purposes. The Company has elected the fair value option to account for originated closed loans intended for sale. Accordingly, changes in fair value relating to loans intended for sale are recorded in earnings and are offset by changes in fair value relating to interest rate lock commitments and forward sales commitments. Gains and losses on residential loan sales (sales proceeds minus carrying amount) are recorded in mortgage banking income. Upfront costs and fees related to items for which the fair value option is elected are recognized in earnings as incurred and are not deferred. Loans Loans are carried at the principal amounts outstanding, or fair value in the case of acquired loans, adjusted by partial charge-offs and net of deferred loan costs or fees. For originated loans, loan fees and certain direct origination costs are deferred and amortized into interest income over the expected term of the loan using the level-yield method. When a loan is paid off, the unamortized portion is recognized in interest income. Interest income on loans is accrued based upon the daily principal amount outstanding except for loans on nonaccrual status. For acquired loans which did not show signs of credit deterioration at acquisition, interest income is also accrued based upon the daily principal amount outstanding and is then further adjusted by the accretion of any discount or amortization of any premium associated with the loan. As a general rule, loans more than 90 days past due with respect to principal or interest are classified as nonaccrual loans, or sooner if management considers such action to be prudent. However, loans that are more than 90 days past due may be kept on an accruing status if the loan is well secured and in the process of collection. The Company may also put a junior lien mortgage on nonaccrual status as a result of delinquency with respect to the first position, which is held by the Bank or by another financial institution, while the junior lien is currently performing. Income accruals are suspended on all nonaccrual loans and all previously accrued and uncollected interest is reversed against current income. A loan remains on nonaccrual status until it becomes current with respect to principal and interest (and in certain instances remains current for up to six months), the loan is liquidated, or when the loan is determined to be uncollectible and is charged-off against the allowance for loan losses. When doubt exists as to the collectability of a loan, any payments received are applied to reduce the recorded investment in the asset to the extent necessary to eliminate such doubt. For all loan portfolios, a charge-off occurs when the Company determines that a specific loan, or portion thereof, is uncollectible. This determination is made based on management's review of specific facts and circumstances of the individual loan, including assessing the viability of the customer’s business or project as a going concern, the expected cash flows to repay the loan, the value of the collateral and the ability and willingness of any guarantors to perform. In cases where a borrower experiences financial difficulties and the Company makes certain concessionary modifications to contractual terms, the loan is classified as a troubled debt restructuring ("TDR"). Modifications may include adjustments to interest rates, extensions of maturity, consumer loans where the borrower's obligations have been effectively discharged through Chapter 7 Bankruptcy and the borrower has not reaffirmed the debt to the Bank, and other actions intended to minimize economic loss and avoid foreclosure or repossession of collateral. The recorded investment of loans classified as TDRs is adjusted to reflect the changes in value, if any, resulting from the granting of a concession. Nonaccrual loans that are restructured remain on nonaccrual for a period of six months to demonstrate that the borrower can meet the restructured terms. If the restructured loan is on accrual status prior to being modified, it is reviewed to determine if the modified loan should remain on accrual status. If the borrower’s ability to meet the revised payment schedule is not reasonably assured, the loan is classified as a nonaccrual loan. Loans classified as TDRs remain classified as such for the life of the loan, except in limited circumstances, when it is determined that the borrower is performing under the modified terms and the restructuring agreement specified an interest rate greater than or equal to an acceptable market rate for a comparable new loan at the time of the restructuring. Acquired loans All acquired loans are recorded at fair value with no carryover of the allowance for loan losses. At acquisition, loans are also reviewed to determine if the loan has evidence of deterioration in credit quality and to review if it is probable, at acquisition, that all contractually required payments will not be collected. Such loans are deemed to be purchased credit impaired ("PCI") loans. Under the accounting model for PCI loans, the excess of cash flows expected to be collected over the carrying amount of the loans, referred to as the "accretable yield", is accreted into interest income over the life of the loans using the effective yield method. Accordingly, PCI loans are not subject to classification as nonaccrual in the same manner as originated loans. Rather, acquired PCI loans are generally considered to be accruing loans because their interest income relates to the accretable yield recognized and not to contractual interest payments at the loan level. The difference between contractually required principal and interest payments and the cash flows expected to be collected, referred to as the "nonaccretable difference", includes estimates of both the impact of prepayments and future credit losses expected to be incurred over the life of the loans. The estimate of cash flows expected to be collected is regularly re-assessed subsequent to acquisition. These re-assessments involve updates, as necessary, of the key assumptions and estimates used in the initial estimate of fair value. Generally speaking, expected cash flows are affected by: • Changes in the expected principal and interest payments over the estimated life - Changes in expected cash flows may be driven by the credit outlook and actions taken with borrowers. Changes in expected future cash flows resulting from loan modifications are included in the assessment of expected cash flows. • Change in prepayment assumptions - Prepayments affect the estimated life of the loans, which may change the amount of interest income expected to be collected. • Change in interest rate indices for variable rate loans - Expected future cash flows are based, as applicable, on the variable rates in effect at the time of the assessment of expected cash flows. A decrease in expected cash flows in subsequent periods may indicate that the loan is impaired which would likely require the recognition of a charge-off against the allowance for loan losses or an establishment of a specific reserve. An increase in expected cash flows in subsequent periods serves, first, to reduce any previously established specific reserve by the increase in the present value of cash flows expected to be collected. Any increase above the previously established specific reserve results in a recalculation of the amount of accretable yield for the loan. The adjustment of accretable yield due to an increase in expected cash flows is accounted for as a change in estimate. The additional cash flows expected to be collected are reclassified from the nonaccretable difference to the accretable yield, and the amount of periodic accretion is adjusted accordingly over the remaining life of the loans. A PCI loan may be resolved either through receipt of payment (in full or in part) from the borrower, the sale of the loan to a third party, or foreclosure of the collateral. In the event of a sale of the loan, a gain or loss on sale would be recognized and reported within noninterest income based on the difference between the sales proceeds and the carrying amount of the loan. For PCI loans accounted for on an individual loan basis and resolved directly with the borrower, any amount received from resolution in excess of the carrying amount of the loan is recognized and reported within interest income. A refinancing or modification of a PCI loan accounted for individually is assessed to determine whether the modification represents a TDR. If the loan is considered to be a TDR, it will be included in the total impaired loans reported by the Company. The loan will continue to recognize interest income based upon the excess of cash flows expected to be collected over the carrying amount of the loan. Allowance for Loan Losses The allowance for loan losses is established based upon the level of estimated probable losses in the current loan portfolio. Loan losses are charged against the allowance when management believes the collectability of a loan balance is doubtful. Subsequent recoveries, if any, are credited to the allowance. The allowance for loan losses is allocated to loan types using both a formula-based approach applied to groups of loans and an analysis of certain individual loans for impairment. The formula-based approach emphasizes loss factors derived from actual historical portfolio loss rates, which are combined with an assessment of certain qualitative factors to determine the allowance amounts allocated to the various loan categories. Allowance amounts are determined based on an estimate of the historical average annual percentage rate of loan loss for each loan category, an estimate of the incurred loss emergence and confirmation period for each loan category, and certain qualitative risk factors considered in the computation of the allowance for loan losses. The qualitative risk factors impacting the inherent risk of loss within the portfolio include the following: • National and local economic and business conditions • Level and trend of delinquencies • Level and trend of charge-offs and recoveries • Trends in volume and terms of loans • Risk selection, lending policy and underwriting standards • Experience and depth of management • Banking industry conditions and other external factors • Concentration risk The formula-based approach evaluates groups of loans with common characteristics, which consist of similar loan types with similar terms and conditions, to determine the appropriate allocation within each portfolio section. This approach incorporates qualitative adjustments based upon management’s assessment of various market and portfolio specific risk factors into its formula-based estimate. Due to the imprecise nature of the loan loss estimation process and ever changing conditions, the qualitative risk attributes may not adequately capture amounts of incurred loss in the formula-based loan loss components used to determine the Bank’s analysis of the appropriateness of the allowance for loan losses. The Bank evaluates certain loans within the commercial and industrial, commercial real estate, commercial construction and small business portfolios individually for specific impairment. A loan is considered impaired when, based on current information and events, it is probable that the Bank will be unable to collect the scheduled payments of principal or interest when due according to the contractual terms of the loan agreement. Factors considered by management in determining impairment include payment status, collateral value, contractual interest rates and the probability of collecting scheduled principal and interest payments when due. Loans that experience insignificant payment delays and payment shortfalls generally are not classified as impaired. Loans are selected for evaluation based upon a change in internal risk rating, occurrence of delinquency, loan classification, troubled debt restructuring or nonaccrual status. A specific allowance amount is allocated to an individual loan when such loan has been deemed impaired and when the amount of the probable loss is able to be estimated. Estimates of loss may be determined by the present value of anticipated future cash flows, the loan’s observable fair market value, or the fair value of the collateral, if the loan is collateral dependent. However, for collateral dependent loans, the amount of the recorded investment in a loan that exceeds the fair value of the collateral less costs to sell is charged-off against the allowance for loan losses in lieu of an allocation of a specific allowance amount when such an amount has been identified definitively as uncollectible. Large groups of small-balance homogeneous loans such as the residential real estate, residential construction, home equity and other consumer portfolios are collectively evaluated for impairment. As such, the Bank does not typically identify individual loans within these groupings as impaired loans for impairment evaluation and disclosure. However, the Bank evaluates all TDRs for impairment on an individual loan basis regardless of loan type. In the ordinary course of business, the Bank enters into commitments to extend credit, commercial letters of credit, and standby letters of credit. Such financial instruments are recorded in the financial statements when they become payable. The credit risk associated with these commitments is evaluated in a manner similar to the allowance for loan losses. The reserve for unfunded lending commitments is included in other liabilities in the balance sheet. At December 31, 2019 and 2018 , the reserve for unfunded loan commitments was $2.1 million and $1.3 million , respectively. Transfers and Servicing of Financial Assets Transfers of financial assets are accounted for as sales when control over the assets has been surrendered. Control over transferred assets is deemed to be surrendered when (1) the assets have been isolated from the Company, (2) the transferee obtains the right (free of conditions that constrain it from taking advantage of that right) to pledge or exchange the transferred assets, and (3) the Company does not maintain effective control over the transferred assets through an agreement to repurchase them before their maturity. Loans held for sale are generally sold with servicing rights released, however if rights are retained, servicing assets are recognized as separate assets. Servicing rights are originally recorded at fair value within other assets, but subsequently are amortized in proportion to and over the period of estimated net servicing income, and are assessed for impairment at each reporting date. Fair value is based on market prices for comparable mortgage servicing contracts, when available, or alternatively, is based on a valuation model that calculates the present value of estimated future net servicing income. The valuation model incorporates assumptions that market participants would use in estimating future net servicing income, such as the cost to service, the discount rate, the custodial earnings rate, an inflation rate, ancillary income, prepayment speeds, default rates and losses. Impairment is determined by stratifying the rights based on predominant characteristics, such as interest rate, loan type and investor type. Impairment is recognized through a valuation allowance, to the extent that fair value is less than the capitalized amount. If the Company later determines that all or a portion of the impairment no longer exists, a reduction of the allowance may be recorded as an increase to income. Servicing fee income is recorded for fees earned for servicing loans for investors. The fees are based on a contractual percentage of the outstanding principal or a fixed amount per loan, and are recorded as income when earned. The amortization of mortgage servicing rights is recorded as a reduction of loan servicing fee income. The Company is also a party to certain instruments with off-balance-sheet risk including certain residential loans sold to investors with recourse. The Company's policy is to record such instruments when funded. Federal Home Loan Bank Stock The Company, as a member of the Federal Home Loan Bank ("FHLB") of Boston, is required to maintain an investment in capital stock of the FHLB. Based on redemption provisions, the stock has no quoted market value and is carried at cost. The Company continually reviews its investment to determine if OTTI exists. The Company reviews recent public filings, rating agency analysis and other factors when making its determination. Bank Premises and Equipment Land is carried at cost. Bank premises and equipment are stated at cost less accumulated depreciation. Depreciation is computed using the straight-line convention method over the estimated useful lives of the assets. Leasehold improvements are amortized over the shorter of the lease terms or the estimated useful lives of the improvements. Expected terms include lease option periods to the extent that the exercise of such options is reasonably assured, not to exceed fifteen years . Goodwill and Other Intangible Assets Goodwill represents the excess of the purchase price over the net fair value of acquired businesses. Goodwill is not amortized and is assigned to one reporting unit. Goodwill is evaluated for impairment at least annually, or more often if warranted, using a combined qualitative and quantitative impairment approach. The initial qualitative approach assesses whether the existence of events or circumstances led to a determination that it is more likely than not that the fair value of a reporting unit is less than its carrying amount. If, after assessing the totality of events and circumstances, the Company determines it is more likely than not that the fair value is less than carrying value, the two step quantitative impairment test is performed. Step one of the quantitative impairment test compares book value to the fair value of the reporting unit. If step one is failed, a detailed step two analysis is performed, which involves measuring the excess of the fair value of the reporting unit, as determined in step one, over the aggregate fair value of the individual assets, liabilities, and identifiable intangibles as if the reporting unit was being acquired in a business combination. Other intangible assets subject to amortization consist of core deposit intangibles, noncompete agreements, customer lists and market-based favorable or unfavorable lease positions at time of acquisition, and are amortized over the estimated lives of the intangibles using a method that approximates the amount of economic benefits that are realized by the Company. Other intangible assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets may not be recoverable. The range of useful lives is as follows: Core deposit intangibles 10 years Noncompete agreement 1 year Customer Lists 12 years Leases 3-30 years The determination of which intangible assets have finite lives is subjective, as is the determination of the amortization period for such intangible assets. Impairment of Long-Lived Assets Other Than Goodwill The Company reviews long-lived assets, including premises and equipment, for impairment whenever events or changes in business circumstances indicate that the remaining useful life may warrant revision or that the carrying amount of the long-lived asset may not be fully recoverable. The Company would perform an undiscounted cash flow analysis to determine if impairment exists. If impairment is determined to exist, any related impairment loss is calculated based on fair value. Impairment losses on assets to be disposed of, if any, are based on the estimated proceeds to be received, less costs of disposal. Cash Surrender Value of Life Insurance Policies Increases in the cash surrender value ("CSV") of life insurance policies, as well as benefits received net of any CSV, are recorded in other noninterest income, and are generally not subject to income taxes. The CSV of the policies is recorded as an asset of the Bank, with liabilities recognized for any split dollar arrangements associated with the policies. The Company reviews the financial strength of the insurance carriers prior to the purchase of life insurance policies and no less than annually thereafter. Regulatory requirements limit the total amount of CSV to be held with any individual carrier to 15% of Tier 1 capital (as defined for regulatory purposes) and the total CSV of all life insurance policies is limited to 25% of Tier 1 capital. Other Real Estate Owned and Other Foreclosed Assets Real estate properties and other assets, which have served as collateral to secure loans, are held for sale and are initially recorded at fair value less estimated costs to sell at the date control is established, resulting in a new cost basis. The amount by which the recorded investment in the loan exceeds the fair value (net of estimated costs to sell) of the foreclosed asset is charged to the allowance for loan losses. Subsequent declines in the fair value of the foreclosed asset below the new cost basis are recorded through the use of a valuation allowance. Subsequent increases in the fair value are recorded as reductions in the valuation allowance, but not below zero. Upon a sale of a foreclosed asset, any excess of the carrying value over the sale proceeds is recognized as a loss on sale. Any excess of sale proceeds over the carrying value of the foreclosed asset is first applied as a recovery to the valuation allowance, if any, with the remainder being recognized as a gain on sale. Operating expenses and changes in the valuation allowance relating to foreclosed assets are included in other noninterest expense. Customer Repurchase Agreements In a security repurchase agreement transaction, the Company will generally sell a security, agreeing to repurchase either the same or substantially identical security on a specified later date, at a greater price than the original sales price. The difference between the sale price and purchase price is the cost of the proceeds, which is recorded as interest expense. The securities underlying the agreements are delivered to counterparties as security for the repurchase obligations. Since the securities are treated as collateral and the agreement does not qualify for a full transfer of effective control, the transactions do not meet the criteria to be classified as a sale, and are therefore considered a secured borrowing transaction for accounting purposes. Derivatives Derivative instruments are carried at fair value in the Company’s financial statements. The accounting for changes in the fair value of a derivative instrument is determined by whether it has been designated and qualifies as part of a hedging relationship, and further, by the type of hedging relationship. At the inception of a hedge, the Company documents certain items, including but not limited to the following: the relationship between hedging instruments and hedged items, the Company's risk management objectives, hedging strategies, and the evaluation of hedge transaction effectiveness. Documentation includes linking all derivatives designated as fair value or cash flow hedges to specific assets and liabilities on the balance sheet or to specific forecasted transactions. For those derivative instruments that are designated and qualify for special hedge accounting, the Company designates the hedging instrument, based upon the exposure being hedged, as either a fair value hedge or a cash flow hedge. For derivative instruments that are designated and qualify as a cash flow hedge (i.e., hedging the exposure to variability in expected future cash flows that is attributable to a particular risk), the effective portion of the gain or loss on the derivative instrument is reported as a component of other comprehensive income, net of related tax. The Company considers any economic mismatch between the hedging instrument and the hedged transaction in its ongoing assessment of hedge effectiveness. If the hedging instrument is not highly effective at achieving offsetting cash flows attributable to the revised contractually specified interest rate(s), hedge accounting will be discontinued. At that time, accumulated other comprehensive income would be frozen and amortized, as long as the forecasted trans

ACQUISITIONS

ACQUISITIONS	12 Months Ended
	Dec. 31, 2019
Business Acquisition [Line Items]
ACQUISITIONS	ACQUISITIONS Blue Hills Bancorp, Inc. On April 1, 2019, the Company completed the acquisition of Blue Hills Bancorp, Inc., parent of Blue Hills Bank (collectively "BHB"). The transaction qualified as a tax-free reorganization for federal income tax purposes and provided a tax-free exchange to Blue Hills Bancorp, Inc. stockholders with respect to the common stock received in the merger. For each share of Blue Hills Bancorp, Inc. common stock, stockholders had the right to receive $5.25 in cash and 0.2308 shares of the Company's stock, with cash paid in lieu of fractional shares. Total consideration of $661.3 million consisted of 6,166,010 shares of the Company's common stock issued, as well as $161.6 million in cash, inclusive of cash in lieu of fractional shares. In addition to increasing its loan and deposit base, the Company will be able to provide a deeper product set to BHB's customers, as well as benefit from increased operating synergies, improving the long-term operating and financial results of the Company. The Company accounted for the BHB acquisition using the acquisition method pursuant to the Business Combinations Topic of the FASB ASC. Accordingly, the Company recorded pre-tax merger and acquisition expenses of $26.0 million during the twelve months ended December 31, 2019 related to the BHB acquisition. Additionally, the acquisition method requires the acquirer to recognize the assets acquired and the liabilities assumed at their fair values as of the acquisition date. The Company used third party valuation specialists to assist in the determination of fair value at the acquisition date. The following table summarizes the estimated fair value of the assets acquired and liabilities assumed as of the date of the acquisition: Net Assets Acquired at Fair Value (Dollars in thousands) Assets Cash $ 56,331 Investments 196,937 Loans 2,073,714 Premises and equipment 24,253 Goodwill 250,101 Core deposit and other intangibles 19,870 Other assets 146,192 Total assets acquired 2,767,398 Liabilities Deposits 1,930,436 Borrowings 124,817 Other liabilities 50,857 Total liabilities assumed 2,106,110 Purchase price $ 661,288 Fair value adjustments to assets acquired and liabilities assumed are generally amortized using either an effective yield or straight-line basis over periods consistent with the average life, useful life and/or contractual term of the related assets and liabilities. Fair values of the major categories of assets acquired and liabilities assumed were determined as follows: Cash and Cash Equivalents The fair values of cash and cash equivalents approximate the respective carrying amounts because the instruments are payable on demand or have short-term maturities. Investments The fair values of securities were based on quoted market prices for comparable securities received from an independent, nationally-recognized, third party pricing service. Prices provided by the independent pricing service were based on recent trading activity and other observable information including, but not limited to, market interest rate curves, referenced credit spreads and estimated prepayment rates where applicable. Loans The loans acquired were recorded at fair value without a carryover of the allowance for loan losses. Fair value of the loans is determined using market participant assumptions in estimating the amount and timing of both principal and interest cash flows expected to be collected, as adjusted for an estimate of future credit losses and prepayments, and then applying a market-based discount rate to those cash flows. The $23.2 million discount on the loans acquired in this transaction was due to anticipated credit loss, as well as considerations for liquidity and market interest rates. In addition, the acquired loans were reviewed to determine if any loans would be deemed PCI, as determined by identifying evidence of deterioration of credit quality at the purchase date combined with an assumption that all contractually required payments will not be collected. The following is a summary of these PCI loans associated with the acquisition as of the date acquired: As of April 1, 2019 (Dollars in thousands) Contractually required principal and interest at acquisition $ 14,849 Contractual cash flows not expected to be collected (5,717 ) Expected cash flows at acquisition 9,132 Interest component of expected cash flows (1,464 ) Basis in PCI loans at acquisition - estimated fair value $ 7,668 Premises and Equipment The fair value of the premises, including land, buildings and improvements, was determined based upon appraisals by licensed real estate appraisers. The appraisals were based upon the best and highest use of the property with final values determined based upon an analysis of the cost, sales comparison and income capitalization approaches for each property appraised. Core Deposit Intangible The fair value of the core deposit intangible is derived by comparing the interest rate and servicing costs that the financial institution pays on the core deposit liability versus the current market rate for alternative sources of financing, while factoring in estimates over the remaining life and attrition rate of the deposit accounts. The intangible asset represents the stable and relatively low cost source of funds that the deposits and accompanying relationships provide the Company, when compared to alternative funding sources. Deposits The fair value of acquired savings and transaction deposit accounts was assumed to approximate the carrying value as these accounts have no stated maturity and are payable on demand. The fair value of time deposits was determined based on the present value of the contractual cash flows over the remaining period to maturity using a market interest rate. Borrowings The fair values of borrowings were derived based upon the present value of the principal and interest payments using a current market discount rate. Selected Pro Forma Results The following summarizes the unaudited pro forma results of operations as if the Company acquired BHB on January 1, 2019 (2018 amounts represent combined results for the Company and BHB). The selected pro forma financial information is presented for illustrative purposes only and is not necessarily indicative of the financial results of the combined companies had the acquisition actually been completed at the beginning of the period presented, nor does it indicate future results for any other interim or full-year period. Year Ended December 31 2019 2018 (Dollars in thousands) Net interest income after provision for loan losses $ 408,918 $ 371,264 Net income $ 129,385 $ 146,178 Included from the pro forma net income for the twelve months ended December 31, 2019 are merger-related costs of $57.3 million , net of tax, recognized by each of the Company and BHB in the aggregate. These costs were primarily made up of severance, contract terminations due to the change in control, Employee stock ownership plan termination expenses, stock compensation and integration costs. MNB Bancorp On November 16, 2018, the Company completed its acquisition of MNB Bancorp Inc. ("MNB Bancorp"), the parent company of The Milford National Bank and Trust Company. The transaction qualified as a tax-free reorganization for federal income tax purposes and MNB Bancorp shareholders received, for each share of MNB Bancorp common stock, the right to receive either $275 in cash per share or 3.55 shares of the Company's common stock (valued at $285.38 per share, based upon the highest trading value of the Company's common stock on November 16, 2018 of $80.39 ). The total deal consideration was $56.1 million and was comprised of 25% cash and 75% stock consideration, which equates to 528,353 shares of the Company's common stock issued to MNB Bancorp shareholders valued at $42.5 million , and $13.6 million in cash, inclusive of cash in lieu of fractional shares. In addition to increasing its loan, deposit and wealth management bases, the Company is able to provide a deeper product set to new customers, as well as benefit from increased operating synergies, improving the long-term operating and financial results of the Company. The Company accounted for the MNB Bancorp acquisition using the acquisition method pursuant to the Business Combinations Topic of the FASB ASC. Accordingly, the Company recorded merger and acquisition expenses of $8.8 million for the year ended December 31, 2018 related to the MNB Bancorp acquisition. Additionally, the acquisition method requires the acquirer to recognize the assets acquired and the liabilities assumed at their fair values as of the acquisition date. The Company used third party valuation specialists as needed to determine fair value at acquisition date. The following table summarizes the estimated fair value of the assets acquired and liabilities assumed as of the date of the acquisition: Net Assets Acquired at Fair Value (Dollars in thousands) Assets Cash $ 6,743 Investments 25,358 Loans 293,498 Premises and equipment 1,904 Goodwill 24,299 Core deposit and other intangibles 8,588 Other assets 8,639 Total assets acquired 369,029 Liabilities Deposits 278,204 Borrowings 33,093 Other liabilities 1,609 Total liabilities assumed 312,906 Purchase price $ 56,123 Fair value adjustments to assets acquired and liabilities assumed are generally amortized using either an effective yield or straight-line basis over periods consistent with the average life, useful life and/or contractual term of the related assets and liabilities. Fair values of the major categories of assets acquired and liabilities assumed were determined as follows: Cash and Cash Equivalents The fair values of cash and cash equivalents approximate the respective carrying amounts because the instruments are payable on demand or have short-term maturities. Loans The loans acquired were recorded at fair value without a carryover of the allowance for loan losses. Fair value of the loans is determined using market participant assumptions in estimating the amount and timing of both principal and interest cash flows expected to be collected, as adjusted for an estimate of future credit losses and prepayments, and then applying a market-based discount rate to those cash flows. The overall discount on the loans acquired in this transaction was due to anticipated credit loss, as well as considerations for liquidity and market interest rates. In addition, the acquired loans were reviewed to determine if any loans would be deemed PCI, as determined by identifying evidence of deterioration of credit quality at the purchase date combined with an assumption that all contractually required payments will not be collected. No loans were deemed to be PCI. Premises and Equipment The fair value of the premises, including land, buildings and improvements, was determined based upon appraisals by licensed real estate appraisers. The appraisals were based upon the best and highest use of the property with final values determined based upon an analysis of the cost, sales comparison and income capitalization approaches for each property appraised. Core Deposit Intangible The fair value of the core deposit intangible is derived by comparing the interest rate and servicing costs that the financial institution pays on the core deposit liability versus the current market rate for alternative sources of financing, while factoring in estimates over the remaining life and attrition rate of the deposit accounts. The intangible asset represents the stable and relatively low cost source of funds that the deposits and accompanying relationships provide the Company, when compared to alternative funding sources. Customer List Intangible The fair value of the customer list intangible is based on the present value of the incremental after-tax cash flows attributable to the trust relationship. Deposits The fair value of acquired savings and transaction deposit accounts was assumed to approximate the carrying value as these accounts have no stated maturity and are payable on demand. The fair value of time deposits was determined based on the present value of the contractual cash flows over the remaining period to maturity using a market interest rate. Borrowings The fair values of borrowings were derived based upon the present value of the principal and interest payments using a current market discount rate. Selected Pro Forma Results The following summarizes the unaudited pro forma results of operations as if the Company acquired MNB Bancorp on January 1, 2018 (2017 amounts represent combined results for the Company and Island Bancorp, Inc. ("Island Bancorp"), which was acquired by the Company on May 12, 2017). The selected pro forma financial information is presented for illustrative purposes only and is not necessarily indicative of the financial results of the combined companies had the acquisition actually been completed at the beginning of the periods presented, nor does it indicate future results for any other interim or full-year period. Years Ended December 31 2018 2017 Net interest income after provision for loan losses $ 304,049 $ 267,104 Net income 122,310 88,518 Included in the pro forma net income for the year ended December 31, 2018 are merger-related costs of $7.5 million , net of tax, recognized by the Company and MNB Bancorp in the aggregate. These costs were primarily made up of contract terminations arising due to the change in control, the acceleration of certain compensation and benefit costs, and other merger expenses.

SECURITIES

SECURITIES	12 Months Ended
	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
SECURITIES	Trading Securities The Company had trading securities of $2.2 million and $1.5 million as of December 31, 2019 and 2018 , respectively. These securities are held in a rabbi trust and will be used for future payments associated with the Company's non-qualified 401(k) Restoration Plan and Non-qualified Deferred Compensation Plan. Equity Securities The Company had equity securities of $21.3 million and $19.5 million as of December 31, 2019 and 2018 , respectively. These securities consist primarily of mutual funds held in a rabbi trust and will be used for future payments associated with the Company’s supplemental executive retirement plans. The following table represents a summary of the gains and losses that relates to equity securities for the periods indicated: Years Ended December 31 2019 2018 2017 Net gains (losses) recognized during the period on equity securities $ 1,566 $ (1,225 ) n/a Less: net gains recognized during the period on equity securities sold during the period 18 874 n/a Unrealized gains (losses) recognized during the reporting period on equity securities still held at the reporting date $ 1,548 $ (2,099 ) n/a Available for Sale and Held to Maturity Securities The following table presents a summary of the amortized cost, gross unrealized holding gains and losses and fair value of securities available for sale and securities held to maturity as of the dates indicated: December 31, 2019 December 31, 2018 Amortized Gross Gross Unrealized Fair Amortized Gross Gross Unrealized Fair (Dollars in thousands) Available for sale securities U.S. government agency securities $ 32,473 $ 642 $ — $ 33,115 $ 32,477 $ — $ (439 ) $ 32,038 Agency mortgage-backed securities 243,548 3,456 (4 ) 247,000 222,491 1,020 (3,406 ) 220,105 Agency collateralized mortgage obligations 87,305 1,225 (19 ) 88,511 138,149 197 (3,435 ) 134,911 State, county, and municipal securities 1,377 19 — 1,396 1,719 16 — 1,735 Single issuer trust preferred securities issued by banks 488 5 — 493 717 — (10 ) 707 Pooled trust preferred securities issued by banks and insurers 1,488 — (374 ) 1,114 1,678 — (349 ) 1,329 Small business administration pooled securities 54,024 771 — 54,795 53,317 — (1,390 ) 51,927 Total available for sale securities 420,703 6,118 (397 ) 426,424 450,548 1,233 (9,029 ) 442,752 Held to maturity securities U.S. government agency securities 12,874 123 — 12,997 — — — — U.S. treasury securities 4,032 21 — 4,053 1,004 11 — 1,015 Agency mortgage-backed securities 397,414 8,445 (57 ) 405,802 252,484 1,548 (3,104 ) 250,928 Agency collateralized mortgage obligations 293,662 4,501 (849 ) 297,314 332,775 869 (6,920 ) 326,724 Single issuer trust preferred securities issued by banks 1,500 — (10 ) 1,490 1,500 — (10 ) 1,490 Small business administration pooled securities 31,324 338 (55 ) 31,607 23,727 105 (349 ) 23,483 Total held to maturity securities 740,806 13,428 (971 ) 753,263 611,490 2,533 (10,383 ) 603,640 Total $ 1,161,509 $ 19,546 $ (1,368 ) $ 1,179,687 $ 1,062,038 $ 3,766 $ (19,412 ) $ 1,046,392 When securities are sold, the adjusted cost of the specific security sold is used to compute the gain or loss on the sale. The actual maturities of certain securities may differ from the contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. A schedule of the contractual maturities of securities available for sale and securities held to maturity as of December 31, 2019 is presented below: Due in one year or less Due after one year to five years Due after five to ten years Due after ten years Total Amortized Cost Fair Value Amortized Cost Fair Value Amortized Cost Fair Value Amortized Cost Fair Value Amortized Cost Fair Value (Dollars in thousands) Available for sale securities U.S. government agency securities $ 10,000 $ 10,003 $ 10,002 $ 10,154 $ 12,471 $ 12,958 $ — $ — $ 32,473 $ 33,115 Agency mortgage-backed securities — — 70,945 71,305 54,798 56,181 117,805 119,514 243,548 247,000 Agency collateralized mortgage obligations — — — — — — 87,305 88,511 87,305 88,511 State, county, and municipal securities — — 1,188 1,193 189 203 — — 1,377 1,396 Single issuer trust preferred securities issued by banks — — — — — — 488 493 488 493 Pooled trust preferred securities issued by banks and insurers — — — — — — 1,488 1,114 1,488 1,114 Small business administration pooled securities — — — — — — 54,024 54,795 54,024 54,795 Total available for sale securities $ 10,000 $ 10,003 $ 82,135 $ 82,652 $ 67,458 $ 69,342 $ 261,110 $ 264,427 $ 420,703 $ 426,424 Held to maturity securities U.S. government agency securities $ 4,962 $ 4,989 $ 7,912 $ 8,008 $ — $ — $ — $ — $ 12,874 $ 12,997 U.S. Treasury securities — — 4,032 4,053 — — — — 4,032 4,053 Agency mortgage-backed securities — — 10,812 10,818 35,656 36,151 350,946 358,833 397,414 405,802 Agency collateralized mortgage obligations — — — — — — 293,662 297,314 293,662 297,314 Single issuer trust preferred securities issued by banks — — — — 1,500 1,490 — — 1,500 1,490 Small business administration pooled securities — — — — — — 31,324 31,607 31,324 31,607 Total held to maturity securities 4,962 4,989 22,756 22,879 37,156 37,641 675,932 687,754 740,806 753,263 Total $ 14,962 $ 14,992 $ 104,891 $ 105,531 $ 104,614 $ 106,983 $ 937,042 $ 952,181 $ 1,161,509 $ 1,179,687 Included in the table above is $17.4 million of callable securities at December 31, 2019 . The carrying value of securities pledged to secure public funds, trust deposits, repurchase agreements and for other purposes, as required or permitted by law, was $375.5 million and $361.1 million at December 31, 2019 and 2018 , respectively. At December 31, 2019 and 2018 , the Company had no investments in obligations of individual states, counties, or municipalities which exceeded 10% of stockholders’ equity . Other-Than-Temporary Impairment The Company continually reviews investment securities for the existence of OTTI, taking into consideration current market conditions, the extent and nature of changes in fair value, issuer rating changes and trends, the credit worthiness of the obligor of the security, volatility of earnings, current analysts’ evaluations, the Company’s intent to sell the security, whether it is more likely than not that the Company will be required to sell the debt security before its anticipated recovery, as well as other qualitative factors. The term "other-than-temporary" is not intended to indicate that the decline is permanent, but indicates that the prospects for a near-term recovery of value are not necessarily favorable, or that there is a lack of evidence to support a realizable value equal to or greater than the carrying value of the investment. The following tables show the gross unrealized losses and fair value of the Company’s investments in an unrealized loss position, which the Company has not deemed to be OTTI, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position: December 31, 2019 Less than 12 months 12 months or longer Total Description of securities # of Fair Value Unrealized Fair Unrealized Fair Value Unrealized (Dollars in thousands) Agency mortgage-backed securities 12 $ 34,009 $ (59 ) $ 243 $ (2 ) $ 34,252 $ (61 ) Agency collateralized mortgage obligations 17 48,476 (215 ) 37,382 (653 ) 85,858 (868 ) Single issuer trust preferred securities issued by banks and insurers 1 — — 1,490 (10 ) 1,490 (10 ) Pooled trust preferred securities issued by banks and insurers 1 — — 1,114 (374 ) 1,114 (374 ) Small business administration pooled securities 1 7,349 (55 ) — — 7,349 (55 ) Total temporarily impaired securities 32 $ 89,834 $ (329 ) $ 40,229 $ (1,039 ) $ 130,063 $ (1,368 ) December 31, 2018 Less than 12 months 12 months or longer Total Description of securities # of Fair Value Unrealized Fair Unrealized Fair Value Unrealized (Dollars in thousands) U.S. government agency securities 3 $ 9,960 $ (43 ) $ 22,078 $ (396 ) $ 32,038 $ (439 ) Agency mortgage-backed securities 144 104,616 (1,363 ) 222,850 (5,147 ) 327,466 (6,510 ) Agency collateralized mortgage obligations 48 57,871 (398 ) 279,229 (9,957 ) 337,100 (10,355 ) Single issuer trust preferred securities issued by banks and insurers 2 2,197 (20 ) — — 2,197 (20 ) Pooled trust preferred securities issued by banks and insurers 1 — — 1,329 (349 ) 1,329 (349 ) Small business administration pooled securities 7 28,257 (662 ) 40,621 (1,077 ) 68,878 (1,739 ) Total temporarily impaired securities 205 $ 202,901 $ (2,486 ) $ 566,107 $ (16,926 ) $ 769,008 $ (19,412 ) The Company does not intend to sell these investments and has determined, based upon available evidence, that it is more likely than not that the Company will not be required to sell each security before the recovery of its amortized cost basis. As a result, the Company does not consider these investments to be OTTI and accordingly, there was no OTTI recorded and no cumulative credit related component of OTTI for the years ended December 31, 2019 , 2018 or 2017 . The Company made this determination by reviewing various qualitative and quantitative factors regarding each investment category, such as current market conditions, extent and nature of changes in fair value, issuer rating changes and trends, volatility of earnings, and current analysts’ evaluations. As a result of the Company’s review of these qualitative and quantitative factors, the causes of the impairments listed in the table above by category are as follows at December 31, 2019 : • Agency Mortgage-Backed Securities, Agency Collateralized Mortgage Obligations and Small Business Administration Pooled Securities: These portfolios have contractual terms that generally do not permit the issuer to settle the securities at a price less than the current par value of the investment. The decline in market value of these securities is attributable to changes in interest rates and not credit quality. Additionally, these securities are implicitly guaranteed by the U.S. government or one of its agencies. • Single Issuer Trust Preferred Securities: This portfolio consists of one security, which is investment grade. The unrealized loss on this security is attributable to the illiquid nature of the trust preferred market in the current economic environment. Management evaluates various financial metrics for the issuers, including regulatory capital ratios of the issuers. • Pooled Trust Preferred Securities: This portfolio consists of one below investment grade security which is performing. The unrealized loss on this security is attributable to the illiquid nature of the trust preferred market in the current economic and regulatory environment. Management evaluates collateral credit and instrument structure, including current and expected deferral and default rates and timing. In addition, discount rates are determined by evaluating comparable spreads observed currently in the market for similar instruments.

LOANS, ALLOWANCE FOR LOAN LOSSE

LOANS, ALLOWANCE FOR LOAN LOSSES AND CREDIT QUALITY	12 Months Ended
	Dec. 31, 2019
Loans, Allowance for Loan Losses and Credit Quality [Abstract]
LOANS, ALLOWANCE FOR LOAN LOSSES AND CREDIT QUALITY	LOANS, ALLOWANCE FOR LOAN LOSSES AND CREDIT QUALITY Allowance for Loan Losses The following tables bifurcate the amount of loans and the allowance allocated to each loan category based on the type of impairment analysis as of the dates indicated: December 31, 2019 Commercial Commercial Commercial Small Residential Home Other Consumer Total (Dollars in thousands) Allowance for loan losses Beginning balance $ 15,760 $ 32,370 $ 5,158 $ 1,756 $ 3,219 $ 5,608 $ 422 $ 64,293 Charge-offs (244 ) (2,614 ) — (509 ) — (240 ) (1,598 ) (5,205 ) Recoveries 1,131 152 — 122 142 318 787 2,652 Provision (benefit) 947 3,027 895 377 79 (110 ) 785 6,000 Ending balance $ 17,594 $ 32,935 $ 6,053 $ 1,746 $ 3,440 $ 5,576 $ 396 $ 67,740 Ending balance: collectively evaluated for impairment $ 17,468 $ 32,887 $ 6,053 $ 1,738 $ 2,803 $ 5,420 $ 391 $ 66,760 Ending balance: individually evaluated for impairment $ 126 $ 48 $ — $ 8 $ 637 $ 156 $ 5 $ 980 Financing receivables ending balance: Collectively evaluated for impairment $ 1,370,580 $ 3,987,848 $ 547,293 $ 173,960 $ 1,571,848 $ 1,127,963 $ 29,663 $ 8,809,155 Individually evaluated for impairment 24,456 8,337 — 537 11,228 4,948 122 49,628 Purchased credit impaired loans — 6,174 — — 7,493 887 302 14,856 Total loans by group $ 1,395,036 $ 4,002,359 $ 547,293 $ 174,497 $ 1,590,569 $ 1,133,798 $ 30,087 $ 8,873,639 (1) December 31, 2018 Commercial Commercial Commercial Small Residential Home Other Consumer Total (Dollars in thousands) Allowance for loan losses Beginning balance $ 13,256 $ 31,453 $ 5,698 $ 1,577 $ 2,822 $ 5,390 $ 447 $ 60,643 Charge-offs (355 ) (82 ) — (372 ) (148 ) (293 ) (1,347 ) (2,597 ) Recoveries 182 188 — 46 12 156 888 1,472 Provision (benefit) 2,677 811 (540 ) 505 533 355 434 4,775 Ending balance $ 15,760 $ 32,370 $ 5,158 $ 1,756 $ 3,219 $ 5,608 $ 422 $ 64,293 Ending balance: collectively evaluated for impairment $ 15,753 $ 32,333 $ 5,158 $ 1,755 $ 2,357 $ 5,444 $ 414 $ 63,214 Ending balance: individually evaluated for impairment $ 7 $ 37 $ — $ 1 $ 862 $ 164 $ 8 $ 1,079 Financing receivables ending balance: Collectively evaluated for impairment $ 1,064,800 $ 3,235,418 $ 365,165 $ 164,135 $ 906,959 $ 1,085,961 $ 15,901 $ 6,838,339 Individually evaluated for impairment 28,829 10,839 — 541 12,706 5,948 197 59,060 Purchased credit impaired loans — 4,991 — — 3,629 175 — 8,795 Total loans by group $ 1,093,629 $ 3,251,248 $ 365,165 $ 164,676 $ 923,294 $ 1,092,084 $ 16,098 $ 6,906,194 (1) December 31, 2017 Commercial Commercial Commercial Small Residential Other Consumer Total (Dollars in thousands) Allowance for loan losses Beginning balance $ 16,921 $ 30,369 $ 4,522 $ 1,502 $ 2,621 $ 5,238 $ 393 $ 61,566 Charge-offs (3,891 ) (39 ) — (302 ) (207 ) (276 ) (1,494 ) (6,209 ) Recoveries 615 385 — 114 31 198 993 2,336 Provision (benefit) (389 ) 738 1,176 263 377 230 555 2,950 Ending balance $ 13,256 $ 31,453 $ 5,698 $ 1,577 $ 2,822 $ 5,390 $ 447 $ 60,643 Ending balance: collectively evaluated for impairment $ 13,246 $ 31,411 $ 5,698 $ 1,576 $ 1,815 $ 5,125 $ 430 $ 59,301 Ending balance: individually evaluated for impairment $ 10 $ 42 $ — $ 1 $ 1,007 $ 265 $ 17 $ 1,342 Financing receivables ending balance: Collectively evaluated for impairment $ 853,885 $ 3,093,945 $ 401,797 $ 131,667 $ 733,809 $ 1,045,053 $ 9,573 $ 6,269,729 Individually evaluated for impairment 34,643 16,638 — 703 13,684 6,826 307 72,801 Purchase credit impaired loans — 5,978 — — 6,836 209 — 13,023 Total loans by group $ 888,528 $ 3,116,561 $ 401,797 $ 132,370 $ 754,329 $ 1,052,088 $ 9,880 $ 6,355,553 (1) (1) The amount of net deferred costs on originated loans included in the ending balance was $7.1 million , at December 31, 2019 and 2018 and $6.1 million and at December 31, 2017 . Net unamortized discounts on acquired loans not deemed to be PCI included in the ending balance were $21.6 million , $15.2 million and $9.4 million at December 31, 2019 , 2018 and 2017 , respectively. For the purpose of estimating the allowance for loan losses, management segregates the loan portfolio into the portfolio segments detailed in the above tables. Each of these loan categories possesses unique risk characteristics that are considered when determining the appropriate level of allowance for each segment. Some of the risk characteristics unique to each loan category include: Commercial Portfolio • Commercial and Industrial : Loans in this category consist of revolving and term loan obligations extended to business and corporate enterprises for the purpose of financing working capital and/or capital investment. Collateral generally consists of pledges of business assets including, but not limited to: accounts receivable, inventory, plant and equipment, or real estate, if applicable. Repayment sources consist of primarily, operating cash flow, and secondarily, liquidation of assets. • Commercial Real Estate : Loans in this category consist of mortgage loans to finance investment in real property such as multi-family residential, commercial/retail, office, industrial, hotels, educational and healthcare facilities and other specific use properties. Loans are typically written with amortizing payment structures. Collateral values are determined based upon third party appraisals and evaluations. Loan to value ratios at origination are governed by established policy and regulatory guidelines. Repayment sources consist of, primarily, cash flow from operating leases and rents and, secondarily, liquidation of assets. • Commercial Construction : Loans in this category consist of short-term construction loans, revolving and nonrevolving credit lines and construction/permanent loans to finance the acquisition, development and construction or rehabilitation of real property. Project types include residential 1-4 family, condominium and multi-family homes, commercial/retail, office, industrial, hotels, educational and healthcare facilities and other specific use properties. Loans may be written with nonamortizing or hybrid payment structures depending upon the type of project. Collateral values are determined based upon third party appraisals and evaluations. Loan to value ratios at origination are governed by established policy and regulatory guidelines. Repayment sources vary depending upon the type of project and may consist of sale or lease of units, operating cash flows or liquidation of other assets. • Small Business: Loans in this category consist of revolving, term loan and mortgage obligations extended to sole proprietors and small businesses for purposes of financing working capital and/or capital investment. Collateral generally consists of pledges of business assets including, but not limited to, accounts receivable, inventory, plant and equipment, or real estate if applicable. Repayment sources consist primarily of operating cash flows and, secondarily, liquidation of assets. For the commercial portfolio it is the Company’s policy to obtain personal guarantees for payment from individuals holding material ownership interests in the borrowing entities. Consumer Portfolio • Residential Real Estate : Residential mortgage loans held in the Company’s portfolio are made to borrowers who demonstrate the ability to make scheduled payments with full consideration to underwriting factors such as current and expected income, employment status, current assets, other financial resources, credit history and the value of the collateral. Collateral consists of mortgage liens on 1-4 family residential properties. Residential mortgage loans also include loans to construct owner-occupied 1-4 family residential properties. • Home Equity : Home equity loans and credit lines are made to qualified individuals and are primarily secured by senior or junior mortgage liens on owner-occupied 1-4 family homes, condominiums or vacation homes. Each home equity loan has a fixed rate and is billed in equal payments comprised of principal and interest. The majority of home equity lines of credit have a variable rate and are billed in interest-only payments during the draw period. At the end of the draw period, the home equity line of credit is billed as a percentage of the then outstanding principal balance plus all accrued interest over a predetermined repayment period, as set forth in the note. Additionally, the Company has the option of renewing each line of credit for additional draw periods. Borrower qualifications include favorable credit history combined with supportive income requirements and combined loan to value ratios within established policy guidelines. • Other Consumer: Other consumer loan products include personal lines of credit and amortizing loans made to qualified individuals for various purposes such as education, debt consolidation, personal expenses or overdraft protection. Borrower qualifications include favorable credit history combined with supportive income and collateral requirements within established policy guidelines. These loans may be secured or unsecured. Credit Quality The Company continually monitors the asset quality of the loan portfolio using all available information. Based on this information, loans demonstrating certain payment issues or other weaknesses may be categorized as adversely risk-rated, delinquent, impaired, nonperforming and/or put on nonaccrual status. Additionally, in the course of resolving such loans, the Company may choose to restructure the contractual terms of certain loans to match the borrower’s ability to repay the loan based on their current financial condition. If a restructured loan meets certain criteria, it may be categorized as a TDR. The Company reviews numerous credit quality indicators when assessing the risk in its loan portfolio. For the commercial portfolio, the Company utilizes a 10-point credit risk-rating system, which assigns a risk-grade to each loan obligation based on a number of quantitative and qualitative factors associated with a commercial or small business loan transaction. Factors considered include industry and market conditions, position within the industry, earnings trends, operating cash flow, asset/liability values, debt capacity, guarantor strength, management and controls, financial reporting, collateral, and other considerations. The risk-ratings categories are defined as follows: • 1- 6 Rating — Pass: Risk-rating grades "1" through "6" comprise those loans ranging from ‘Substantially Risk Free’ which indicates borrowers are of unquestioned credit standing and the pinnacle of credit quality, well established companies with a very strong financial condition, and loans fully secured by cash collateral, through ‘Acceptable Risk’, which indicates borrowers may exhibit declining earnings, strained cash flow, increasing or above average leverage and/or weakening market fundamentals that indicate below average asset quality, margins and market share. Collateral coverage is protective. • 7 Rating — Potential Weakness: Borrowers exhibit potential credit weaknesses or downward trends deserving management’s close attention. If not checked or corrected, these trends will weaken the Company’s asset and position. While potentially weak, currently these borrowers are marginally acceptable; no loss of principal or interest is envisioned. • 8 Rating — Definite Weakness Loss Unlikely: Borrowers exhibit well defined weaknesses that jeopardize the orderly liquidation of debt. Loans may be inadequately protected by the current net worth and paying capacity of the obligor or by the collateral pledged, if any. Normal repayment from the borrower is in jeopardy, although no loss of principal is envisioned. However, there is a distinct possibility that a partial loss of interest and/or principal will occur if the deficiencies are not corrected. Collateral coverage may be inadequate to cover the principal obligation. • 9 Rating — Partial Loss Probable: Borrowers exhibit well defined weaknesses that jeopardize the orderly liquidation of debt with the added provision that the weaknesses make collection of the debt in full, on the basis of currently existing facts, conditions, and values, highly questionable and improbable. Serious problems exist to the point where partial loss of principal is likely. • 10 Rating — Definite Loss: Borrowers deemed incapable of repayment. Loans to such borrowers are considered uncollectible and of such little value that continuation as active assets of the Company is not warranted. The credit quality of the commercial loan portfolio is actively monitored and any changes in credit quality are reflected in risk-rating changes. Risk-ratings are assigned or reviewed for all new loans, when advancing significant additions to existing relationships (over $50,000 ), at least quarterly for all actively managed loans, and any time a significant event occurs, including at renewal of the loan. The Company utilizes a comprehensive strategy for monitoring commercial credit quality. Actively managed commercial borrowers are required to provide updated financial information at least annually which is carefully evaluated for any changes in credit quality. Larger loan relationships are subject to a full annual credit review by an experienced credit analysis group, while continuous portfolio monitoring techniques are employed to evaluate changes in credit quality for smaller loan relationships. Additionally, the Company retains an independent loan review firm to evaluate the credit quality of the commercial loan portfolio. The independent loan review process achieves significant penetration into the commercial loan portfolio and reports the results of these reviews to the Audit Committee of the Board of Directors on a quarterly basis. The following tables detail the amount of outstanding principal balances relative to each of the risk-rating categories for the Company’s commercial portfolio: December 31, 2019 Category Risk Commercial and Commercial Real Commercial Small Business Total (Dollars in thousands) Pass 1 - 6 $ 1,274,155 $ 3,860,555 $ 542,608 $ 171,213 $ 5,848,531 Potential weakness 7 63,485 97,268 2,247 1,416 164,416 Definite weakness - loss unlikely 8 57,396 44,536 2,438 1,868 106,238 Partial loss probable 9 — — — — — Definite loss 10 — — — — — Total $ 1,395,036 $ 4,002,359 $ 547,293 $ 174,497 $ 6,119,185 December 31, 2018 Category Risk Commercial and Commercial Real Commercial Small Business Total (Dollars in thousands) Pass 1 - 6 $ 1,014,370 $ 3,156,989 $ 361,884 $ 161,851 $ 4,695,094 Potential weakness 7 16,860 56,840 298 888 74,886 Definite weakness - loss unlikely 8 58,909 37,419 2,983 1,937 101,248 Partial loss probable 9 3,490 — — — 3,490 Definite loss 10 — — — — — Total $ 1,093,629 $ 3,251,248 $ 365,165 $ 164,676 $ 4,874,718 For the Company’s consumer portfolio, the quality of the loan is best indicated by the repayment performance of an individual borrower. However, the Company does supplement performance data with current Fair Isaac Corporation ("FICO") scores and Loan to Value ("LTV") estimates. Current FICO data is purchased and appended to all consumer loans on a regular basis. In addition, automated valuation services and broker opinions of value are used to supplement original value data for the residential and home equity portfolios, periodically. The following table shows the weighted average FICO scores and the weighted average combined LTV ratios as of the dates indicated below: December 31 2019 2018 Residential portfolio FICO score (re-scored) (1) 749 749 LTV (re-valued) (2) 59.0 % 58.6 % Home equity portfolio FICO score (re-scored) (1) 767 767 LTV (re-valued) (2) (3) 46.6 % 49.3 % (1) The average FICO scores are based upon rescores available from November and origination score data for loans booked in December. (2) The combined LTV ratios are based upon updated automated valuations as of November, when available, and/or the most current valuation data available. The updated automated valuations provide new information on loans that may be available since the previous valuation was obtained. If no new information is available, the valuation will default to the previously obtained data or most recent appraisal. (3) For home equity loans and lines in a subordinate lien, the LTV data represents a combined LTV, taking into account the senior lien data for loans and lines. Asset Quality The Company’s philosophy toward managing its loan portfolios is predicated upon careful monitoring, which stresses early detection and response to delinquent and default situations. Delinquent loans are managed by a team of collection specialists and the Company seeks to make arrangements to resolve any delinquent or default situation over the shortest possible time frame. As a general rule, loans more than 90 days past due with respect to principal or interest are classified as nonaccrual loans. The Company also may use discretion regarding the accrual status of other loans over 90 days delinquent if the loan is well secured and in process of collection. The following table shows the carrying value of nonaccrual loans at the dates indicated: December 31 2019 2018 (Dollars in thousands) Commercial and industrial $ 22,574 $ 26,310 Commercial real estate 3,016 3,015 Commercial construction — 311 Small business 311 235 Residential real estate 13,360 8,251 Home equity 6,570 7,278 Other consumer 61 13 Total nonaccrual loans (1) $ 45,892 $ 45,413 (1) Included in these amounts were $24.8 million and $29.3 million of nonaccruing TDRs at December 31, 2019 and 2018 , respectively. The following table shows information regarding foreclosed residential real estate property at the date indicated: December 31, 2019 December 31, 2018 (Dollars in thousands) Foreclosed residential real estate property held by the creditor $ — $ — Recorded investment in mortgage loans collateralized by residential real estate property that are in the process of foreclosure $ 3,294 $ 3,174 The following table shows the age analysis of past due financing receivables as of the dates indicated: December 31, 2019 30-59 days 60-89 days 90 days or more Total Past Due Current Total Recorded Number Principal Number Principal Number Principal Number Principal (Dollars in thousands) Commercial and industrial 1 $ 253 2 $ 323 5 $ 760 8 $ 1,336 $ 1,393,700 $ 1,395,036 $ — Commercial real estate 7 1,690 1 194 8 2,038 16 3,922 3,998,437 4,002,359 218 (2) Commercial construction 1 560 — — — — 1 560 546,733 547,293 — Small business 11 837 3 15 6 115 20 967 173,530 174,497 — Residential real estate 17 2,237 17 3,055 38 7,020 72 12,312 1,578,257 1,590,569 1,652 (2) Home equity 23 1,689 8 524 40 3,854 71 6,067 1,127,731 1,133,798 265 (2) Other consumer (1) 387 245 12 44 16 32 415 321 29,766 30,087 22 Total 447 $ 7,511 43 $ 4,155 113 $ 13,819 603 $ 25,485 $ 8,848,154 $ 8,873,639 $ 2,157 December 31, 2018 30-59 days 60-89 days 90 days or more Total Past Due Current Total Recorded Number Principal Number Principal Number Principal Number Principal (Dollars in thousands) Commercial and industrial — $ — 4 $ 382 11 $ 26,311 15 $ 26,693 $ 1,066,936 $ 1,093,629 $ — Commercial real estate 9 1,627 — — 8 2,250 17 3,877 3,247,371 3,251,248 — Commercial construction 1 1,271 — — 1 311 2 1,582 363,583 365,165 — Small business 15 506 19 87 24 162 58 755 163,921 164,676 — Residential real estate 23 3,486 6 521 25 4,382 54 8,389 914,905 923,294 — Home equity 22 1,331 12 855 29 2,663 63 4,849 1,087,235 1,092,084 — Other consumer (1) 330 181 15 9 12 13 357 203 15,895 16,098 5 Total 400 $ 8,402 56 $ 1,854 110 $ 36,092 566 $ 46,348 $ 6,859,846 $ 6,906,194 $ 5 (1) Other consumer portfolio is inclusive of deposit account overdrafts recorded as loan balances. (2) Represents purchased credit impaired loans that are accruing interest due to expectations of future cash collections. Troubled Debt Restructurings In the course of resolving nonperforming loans, the Bank may choose to restructure the contractual terms of certain loans. The Bank attempts to work out an alternative payment schedule with the borrower in order to avoid foreclosure actions. Any loans that are modified are reviewed by the Bank to identify if a TDR has occurred, which is when, for economic or legal reasons related to a borrower’s financial difficulties, the Bank 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 status 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. The following table shows the Company’s total TDRs and other pertinent information as of the dates indicated: December 31 2019 2018 (Dollars in thousands) TDRs on accrual status $ 19,599 $ 23,849 TDRs on nonaccrual status 24,766 29,348 Total TDRs $ 44,365 $ 53,197 Amount of specific reserves included in the allowance for loan loss associated with TDRs: $ 855 $ 1,079 Additional commitments to lend to a borrower who has been a party to a TDR: $ 63 $ 982 The Company’s policy is to have any restructured loan which is on nonaccrual status prior to being modified remain on nonaccrual status for six months subsequent to being modified before management considers its return to accrual status. If the restructured loan is on accrual status prior to being modified, it is reviewed to determine if the modified loan should remain on accrual status. Additionally, loans classified as TDRs are adjusted to reflect the changes in value of the recorded investment in the loan, if any, resulting from the granting of a concession. For all residential loan modifications, the borrower must perform during a 90 day trial period before the modification is finalized. The following table shows the modifications which occurred during the periods indicated and the change in the recorded investment subsequent to the modifications occurring: Years Ended December 31 2019 Number Pre-Modification Post-Modification (Dollars in thousands) Troubled debt restructurings Commercial and industrial 3 $ 268 $ 268 Commercial real estate 4 819 819 Small business 1 14 14 Residential real estate 3 967 1,009 Home equity 2 121 121 Total 13 $ 2,189 $ 2,231 2018 Troubled debt restructurings Commercial and industrial (1) 12 $ 35,688 $ 39,224 Commercial real estate 3 1,600 1,600 Residential real estate 5 1,048 1,071 Home equity 9 562 562 Total 29 $ 38,898 $ 42,457 2017 Troubled debt restructurings Commercial and industrial 12 $ 1,787 $ 1,787 Commercial real estate 6 2,705 2,705 Small business 9 369 369 Residential real estate 10 1,284 1,326 Home equity 17 1,985 1,988 Total 54 $ 8,130 $ 8,175 (1) The pre-modification and post-modification balances represent the legal principal balance of the loan. These amounts may show an increase when modifications include a capitalization of interest and/or professional fees. The following table shows the Company’s post-modification balance of TDRs listed by type of modification for the periods indicated: Years Ended December 31 2019 2018 2017 (Dollars in thousands) Extended maturity $ 1,565 $ 2,878 $ 5,881 Adjusted interest rate 150 57 — Combination rate and maturity 441 38,812 568 Court ordered concession 75 710 1,726 Total $ 2,231 $ 42,457 $ 8,175 The Company considers a loan to have defaulted when it reaches 90 days past due. As of December 31, 2019 and 2018, there were no loans modified during the prior twelve months that subsequently defaulted. During the twelve months ended December 31, 2017 there was one commercial and industrial loan that was modified during the proceeding twelve month period, with a recorded investment of 122,000 , which subsequently defaulted. All TDR loans are considered impaired and therefore are subject to a specific review for impairment. The impairment analysis appropriately discounts the present value of the anticipated cash flows by the loan’s contractual rate of interest in effect prior to the loan’s modification. The amount of impairment, if any, is recorded as a specific loss allocation to each individual loan in the allowance for loan losses. Commercial loans (commercial and industrial, commercial construction, commercial real estate and small business loans), residential loans, and home equity loans that have been classified as TDRs and which subsequently default are reviewed to determine if the loan should be deemed collateral dependent. In such an instance, any shortfall between the value of the collateral and the carrying value of the loan is determined by measuring the recorded investment in the loan against the fair value of the collateral less costs to sell. The Company charges off the amount of any confirmed loan loss in the period when the loans, or portion of loans, are deemed uncollectible. Smaller balance consumer TDR loans are reviewed for performance to determine when a charge-off is appropriate. Impaired Loans A loan is considered impaired when, based on current information and events, it is probable that the Company will be unable to collect the scheduled payments of principal or interest when due according to the contractual terms of the loan agreement. Factors considered by management in determining impairment include payment status, collateral value, and the probability of collecting scheduled principal and interest payments when due. Loans that experience insignificant payment delays and payment shortfalls generally are not classified as impaired. Management determines the significance of payment delays and payment shortfalls on a case-by-case basis, taking into consideration all of the circumstances surrounding the loan and the borrower, including the length of the delay, the reasons for the delay, the borrower’s prior payment record, and the amount of the shortfall in relation to the principal and interest owed. The tables below set forth information regarding the Company’s impaired loans. The information for average recorded investment and interest income recognized is reflective of the full period being presented and does not take into account the date at which a loan was deemed to be impaired. See information below as of the dates indicated: As of and For the Years Ended December 31 2019 Recorded Unpaid Related Average Interest Income Recognized (Dollars in thousands) With no related allowance recorded Commercial and industrial $ 23,786 $ 34,970 $ — $ 27,056 $ 136 Commercial real estate 6,213 12,101 — 12,595 523 Small business 469 484 — 471 22 Residential real estate 4,976 5,123 — 5,045 222 Home equity 3,764 3,893 — 3,869 184 Other consumer 34 34 — 41 3 Subtotal 39,242 56,605 — 49,077 1,090 With an allowance recorded Commercial and industrial 670 670 126 718 29 Commercial real estate 2,124 2,124 48 2,176 122 Small business 68 105 8 74 2 Residential real estate 6,252 7,163 637 6,326 239 Home equity 1,184 1,382 156 1,214 52 Other consumer 88 91 5 97 3 Subtotal 10,386 11,535 980 10,605 447 Total $ 49,628 $ 68,140 $ 980 $ 59,682 $ 1,537 2018 Recorded Unpaid Related Average Interest (Dollars in thousands) With no related allowance recorded Commercial and industrial $ 28,459 $ 35,913 $ — $ 31,117 $ 142 Commercial real estate 9,552 9,832 — 10,561 519 Small business 358 439 — 401 14 Residential real estate 4,518 4,686 — 4,597 212 Home equity 4,957 5,199 — 5,230 220 Other consumer 56 56 — 64 4 Subtotal 47,900 56,125 — 51,970 1,111 With an allowance recorded Commercial and industrial 370 370 7 385 19 Commercial real estate 1,287 1,287 37 1,311 74 Small business 183 223 1 225 13 Residential real estate 8,188 9,217 862 8,459 289 Home equity 991 1,149 164 1,018 43 Other consumer 141 143 8 154 5 Subtotal 11,160 12,389 1,079 11,552 443 Total $ 59,060 $ 68,514 $ 1,079 $ 63,522 $ 1,554 2017 Recorded Unpaid Related Average Interest (Dollars in thousands) With no related allowance recorded Commercial and industrial $ 34,267 $ 38,329 $ — $ 36,631 $ 446 Commercial real estate 13,245 14,374 — 13,683 559 Small business 556 619 — 569 21 Residential real estate 4,264 4,397 — 4,332 218 Home equity 4,950 5,056 — 5,063 198 Other consumer 91 92 — 102 7 Subtotal 57,373 62,867 — 60,380 1,449 With an allowance recorded Commercial and industrial 376 376 10 391 19 Commercial real estate 3,393 3,399 42 3,447 198 Small business 147 153 1 238 14 Residential real estate 9,420 10,154 1,007 9,575 284 Home equity 1,876 2,110 265 1,916 55 Other consumer 216 217 17 233 7 Subtotal 15,428 16,409 1,342 15,800 577 Total $ 72,801 $ 79,276 $ 1,342 $ 76,180 $ 2,026 Purchased Credit Impaired Loans Certain loans acquired by the Company may have shown evidence of deterioration of credit quality since origination and it was therefore deemed unlikely that the Company would be able to collect all contractually required payments. As such, these loans were deemed to be PCI loans and the carrying value and prospective income recognition are predicated upon future cash flows expected to be collected. The following table displays certain information pertaining to PCI loans at the dates indicated: December 31 2019 2018 (Dollars in thousands) Outstanding balance $ 18,358 $ 9,749 Carrying amount $ 14,856 $ 8,795 The following table summarizes activity in the accretable yield for the PCI loan portfolio: 2019 2018 (Dollars in thousands) Beginning balance $ 1,191 $ 1,791 Acquisition 1,464 — Accretion (1,751 ) (1,135 ) Other change in expected cash flows (1) 803 310 Reclassification from nonaccretable difference for loans which have paid off (2) 227 225 Ending balance $ 1,934 $ 1,191 (1) Represents changes in cash flows expected to be collected resulting in increased interest income as a prospective yield adjustment over the remaining life of the loan(s). (2) Results in increased income during the period when a loan pays off at amount greater than originally expected.

BANK PREMISES AND EQUIPMENT

BANK PREMISES AND EQUIPMENT	12 Months Ended
	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
BANK PREMISES AND EQUIPMENT	BANK PREMISES AND EQUIPMENT Bank premises and equipment at December 31, were as follows: 2019 2018 Estimated (Dollars in thousands) (In years) Cost Land $ 32,619 $ 24,502 n/a Bank premises 62,455 53,052 5-40 Leasehold improvements 35,498 27,615 1-27 Furniture and equipment 77,705 66,974 2-12 Leased equipment 10,644 10,644 7 Total cost 218,921 182,787 Accumulated depreciation (95,247 ) (85,206 ) Net bank premises and equipment $ 123,674 $ 97,581 Depreciation expense related to bank premises and equipment was $11.4 million in 2019 , $9.1 million in 2018 , and $8.5 million in 2017 , respectively, primarily included in occupancy and equipment expenses. Depreciation expense relating to computer software is included within other noninterest expense. During 2017, the Company purchased equipment that was subject to a master lease agreement with a third party lessee. As such, the Company assumed the role of lessor in conjunction with the purchase, which was deemed to be an operating lease for accounting purposes. The Company purchased a total of $10.6 million of equipment subject to the lease agreement in 2017 . In addition, the Company recognized rental income of $1.6 million in each of the years ended December 31, 2019 and 2018 , and $1.3 million in the year ended December 31, 2017. Included in the total above is depreciation expense of $1.3 million for each of the years ended December 31, 2019 and 2018 , and $939,000 for the year ended December 31, 2017 related to the leased equipment.

GOODWILL AND IDENTIFIABLE INTAN

GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS	12 Months Ended
	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS	GOODWILL AND OTHER INTANGIBLE ASSETS The following table sets forth the carrying value of goodwill and other intangible assets, net of accumulated amortization, at December 31: 2019 2018 (Dollars in thousands) Balances not subject to amortization Goodwill $ 506,206 $ 256,105 Balances subject to amortization Core deposit intangibles 28,016 13,692 Other intangible assets 1,270 1,558 Total other intangible assets 29,286 15,250 Total goodwill and other intangible assets $ 535,492 $ 271,355 The changes in the carrying value of goodwill for the periods indicated were as follows: 2019 2018 (Dollars in thousands) Balance at beginning of year $ 256,105 $ 231,806 Acquisitions 250,101 24,299 Balance at end of year $ 506,206 $ 256,105 The gross carrying amount and accumulated amortization of other intangible assets were as follows at the dates indicated: December 31 2019 2018 Gross Accumulated Net Gross Accumulated Net (Dollars in thousands) Core deposit intangibles $ 45,245 $ (17,229 ) $ 28,016 $ 34,137 $ (20,445 ) $ 13,692 Other intangible assets 3,338 (2,068 ) 1,270 3,103 (1,545 ) 1,558 Total $ 48,583 $ (19,297 ) $ 29,286 $ 37,240 $ (21,990 ) $ 15,250 Amortization of intangible assets was $6.8 million , $2.7 million , and $3.5 million at December 31, 2019 , 2018 , and 2017 , respectively. The following table sets forth the estimated annual amortization expense of intangible assets for each of the next five years: Year Amount (Dollars in thousands) 2020 $ 6,179 2021 $ 5,315 2022 $ 4,539 2023 $ 3,948 2024 $ 3,162 The original weighted average amortization period for intangible assets is 9.8 years .

DEPOSITS

DEPOSITS	12 Months Ended
	Dec. 31, 2019
Banking and Thrift [Abstract]
DEPOSITS	DEPOSITS The following is a summary of the scheduled maturities of time deposits as of December 31: 2019 2018 (Dollars in thousands) 1 year or less $ 1,097,407 78.6 % $ 511,292 71.9 % Over 1 year to 2 years 204,690 14.7 % 111,487 15.7 % Over 2 years to 3 years 55,615 4.0 % 41,523 5.8 % Over 3 years to 4 years 24,038 1.7 % 27,040 3.8 % Over 4 years to 5 years 13,565 1.0 % 19,761 2.8 % Total $ 1,395,315 100.0 % $ 711,103 100.0 % The amount of overdraft deposits that were reclassified to the loan category were $5.0 million and $3.3 million at December 31, 2019 and 2018 , respectively. The Company has pledged assets as collateral covering certain deposits in the amount of $323.1 million and $356.8 million at December 31, 2019 and 2018 , respectively. The Bank's deposit accounts are insured to the maximum extent permitted by law by the Deposit Insurance Fund which is administered by the FDIC. The FDIC offers insurance coverage on deposits up to the federally insured limit of $250,000. The amount of time deposit accounts equal to or greater than $250,000 as of December 31, 2019 and 2018 is $244.7 million and $104.9 million

BORROWINGS

BORROWINGS	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
BORROWINGS	BORROWINGS Federal Home Loan Bank Borrowings Advances payable to the Federal Home Loan Bank as of December 31 of the years below are summarized as follows: 2019 2018 Weighted Weighted Average Average Total Contractual Total Contractual Outstanding Rate Outstanding Rate (Dollars in thousands) Stated Maturity 2019 $ — — % $ 147,046 2.68 % 2020 104,976 1.79 % — — % 2021 10,042 2.95 % — — % Subtotal 115,018 1.89 % 147,046 2.68 % Amortizing advances 730 760 Total Federal Home Loan Bank Advances $ 115,748 $ 147,806 To manage the interest rate risk of these advances, the Company may enter into interest rate swap agreements which effectively fix the rate of the borrowing. Inclusive of the impact of these swap arrangements, the weighted average rate of the FHLB borrowings was 1.88% and 2.55% at December 31, 2019 and 2018 , respectively. The Company’s FHLB advances are collateralized by a blanket pledge agreement on the Bank’s FHLB stock, certain qualified investment securities, deposits at the FHLB, residential mortgages, and by certain commercial real estate loans held in the Bank’s portfolio. The carrying value of the loans pledged as collateral for these borrowings totaled $2.5 billion and $1.6 billion at December 31, 2019 and 2018 , respectively. The Bank’s unused remaining available borrowing capacity at the FHLB was approximately $1.6 billion and $953.5 million at December 31, 2019 and 2018 , respectively, inclusive of a $5.0 million line of credit. At December 31, 2019 and 2018 , the Company had sufficient collateral at the FHLB to support its obligations and was in compliance with the FHLB's collateral pledging program. Short-Term Debt Excluding FHLB borrowings included in the table above, the Company had no short-term borrowings at December 31, 2019 and December 31, 2018 . The Company's short-term borrowings at December 31, 2017 consisted of customer repurchase agreements of $162.7 million which were discontinued and transitioned to a deposit product offering in the fourth quarter of 2018. In addition, on March 28, 2019, the Company entered into a credit facility for a principal amount of $50.0 million senior unsecured revolving loan credit facility, bearing interest at an interest rate equal to the one-month LIBOR rate plus 1.15% . The Company used the proceeds of these borrowings for funding needs related to the second quarter closing of BHB. During the second quarter of 2019, the Company repaid in full the entire $50.0 million amount of the senior unsecured revolving loan. The interest expense on short-term borrowings was $104,000 , $248,000 , and $257,000 for the years ended December 31, 2019 , 2018 , and 2017 , respectively Long-Term Debt The following table summarizes long-term debt, net of debt issuances costs, as of the dates indicated: December 31 2019 2018 (Dollars in thousands) Long term borrowings, net $ 74,906 $ — Junior subordinated debentures Capital Trust V 51,507 51,505 Slades Ferry Trust I — 10,234 Central Trust I 5,258 5,258 Central Trust II 6,083 6,083 East Main Street Trust — 3,093 Subordinated debentures 49,601 34,728 Total long-term debt $ 187,355 $ 110,901 The interest expense on long-term debt was $8.2 million , $4.2 million , and $3.9 million for the years ended December 31, 2019 , 2018 , and 2017 , respectively. Long-term borrowings: During the first quarter of 2019 the Company entered into a $75.0 million senior unsecured term loan credit facility. Advances under the term loan facility bear interest at an interest rate equal to one-month LIBOR plus 1.25% ( 3.19% at December 31, 2019). This term loan facility is due and payable in full on March 28, 2022. Junior Subordinated Debentures : The junior subordinated debentures are issued to various trust subsidiaries of the Company. These trusts are considered to be variable interest entities for which the Company is not the primary beneficiary, and therefore the accounts of the trusts are not included in the Company’s consolidated financial statements. These trusts were formed for the purpose of issuing trust preferred securities, which were then sold in a private placement offering. The proceeds from the sale of the securities and the issuance of common stock by these trusts were invested in these Junior Subordinated Debentures issued by the Company. For regulatory purposes, bank holding companies are allowed to include trust preferred securities in Tier 1 capital up to a certain limit. Provisions in the Dodd-Frank Act generally exclude trust preferred securities from Tier 1 capital, however, holding companies with consolidated assets of less than $15 billion, such as the Company, are able to continue to include these instruments in Tier 1 capital, but no such securities issued in the future will count as Tier 1 capital. Information relating to these trust preferred securities is as follows: Trust Description of Capital Securities Capital Trust V $50.0 million due in 2037, interest at a variable rate of 3 month LIBOR plus 1.48% (3.37% at December 31, 2019),which, effective on January 17, 2017, has been converted to a fixed rate of 2.84% through the use of an interest rate swap. Central Trust I $5.1 million due in 2034, bearing interest at a variable rate of 3 month LIBOR plus 2.44% (4.33% at December 31, 2019). These securities are callable quarterly, until maturity. Central Trust II $5.9 million due in 2037, bearing interest at a variable rate of 3 month LIBOR plus 1.65% (3.54% at December 31, 2019). These securities are callable quarterly, until maturity. All obligations under these trust preferred securities are unconditionally guaranteed by the Company. Subordinated Debentures : At December 31, 2019 and 2018 there was $50.0 million and $35.0 million , respectively, of outstanding subordinated debentures at the bank holding company. On March 14, 2019 the Company issued $50.0 million in aggregate principal amount in a private placement transaction to institutional accredited investors. The subordinated debentures mature on March 15, 2029. However, with regulatory approval, the Company may redeem the subordinated debentures without penalty at any scheduled payment date on or after March 15, 2024 with 30 days notice. The subordinated debentures carry a fixed rate of interest of 4.75% through March 15, 2024, after which interest converts to a variable rate of the then current three-month LIBOR rate plus 219 basis points. The Company also had outstanding $35.0 million of subordinated debentures that were issued to several investors via private placement on November 17, 2014. The subordinated debentures were to mature on November 15, 2024, however with regulatory approval, the Bank could redeem the subordinated debentures without penalty at any scheduled payment date on or after November 15, 2019 with 30 days' notice. Accordingly, in November 2019 the Company redeemed the $35.0 million of subordinated debentures at the bank holding company with regulatory approval. The interest rate was fixed at 4.75% through November 15, 2019. The following table sets forth the contractual maturities of long-term debt over the next five years: 2020 2021 2022 2023 2024 Thereafter Total (Dollars in thousands) Long term borrowings $ — $ — $ 75,000 $ — $ — $ — $ 75,000 Junior subordinated debentures Capital trust V — — — — — 51,547 51,547 Central trust I — — — — — 5,258 5,258 Central trust II — — — — — 6,083 6,083 Subordinated debentures — — — — — 50,000 50,000 Total (1) $ — $ — $ 75,000 $ — $ — $ 112,888 $ 187,888 (1) Amounts in this table are presented on a gross basis, and do not include the capitalized issuance costs as presented in the Company's Consolidated Balance Sheet.

EARNINGS PER SHARE

EARNINGS PER SHARE	12 Months Ended
	Dec. 31, 2019
Earnings Per Share [Abstract]
EARNINGS PER SHARE	Earnings per share consisted of the following components for the years ended December 31: 2019 2018 2017 (Dollars in thousands, except per share data) Net income $ 165,175 $ 121,622 $ 87,204 Weighted Average Shares Basic shares 32,810,433 27,592,380 27,294,028 Effect of dilutive securities 45,801 61,428 78,076 Diluted shares 32,856,234 27,653,808 27,372,104 Net income per share Basic EPS $ 5.03 $ 4.41 $ 3.19 Effect of dilutive securities — (0.01 ) — Diluted EPS $ 5.03 $ 4.40 $ 3.19 For the years ended December 31, 2019 and 2018 , there were no options to purchase common stock and no shares of performance-based restricted stock that were excluded from the calculation of diluted earnings per share because they were anti-dilutive. For the year ended December 31, 2017 , there were 103 options to purchase common stock and no

STOCK BASED COMPENSATION

STOCK BASED COMPENSATION	12 Months Ended
	Dec. 31, 2019
Share-based Payment Arrangement [Abstract]
STOCK BASED COMPENSATION	The Company's stock based plans include the Second Amended and Restated 2005 Employee Stock Plan (the "2005 Plan") and the 2018 Non-Employee Director Stock Plan (the "2018 Plan"), which have been approved by the Company’s Board of Directors and shareholders. The 2010 Non-Employee Director Stock Plan (the "2010 Plan") expired on May 17, 2018, and as such the Company may only award shares from the 2005 Plan or the 2018 Plan. These shares may be awarded as either stock option awards or restricted stock awards from its pool of authorized but unissued shares. The following table presents the amount of cumulatively granted stock option awards and restricted stock awards, net of forfeitures and expirations, granted through December 31, 2019 : Authorized Awards Cumulatively Granted, Net of Total Authorized Stock Restricted 2005 Plan 1,650,000 387,258 810,381 1,197,639 452,361 2010 Plan 314,600 46,500 93,245 139,745 — (1) 2018 Plan 300,000 — 12,500 12,500 287,500 (1) (1) The Company may award up to a total of 300,000 shares from the 2018 Plan, inclusive of 174,855 shares that were Authorized but Unissued in the 2010 Plan, and were transferred from the 2010 Plan to the 2018 Plan. Due to this transfer, there are no available shares remaining to be issued from the 2010 Plan. The following table presents the pre-tax expense associated with stock option and restricted stock awards and the related tax benefits recognized for the periods presented: Years Ended December 31 2019 2018 2017 (Dollars in thousands) Stock based compensation expense Restricted stock awards (1) $ 3,679 $ 3,299 $ 2,730 Directors’ fee expense (2) Stock options 23 66 76 Restricted stock awards 701 860 527 Total stock based award expense $ 4,403 $ 4,225 $ 3,333 Related tax benefits recognized in earnings $ 1,238 $ 1,188 $ 1,362 (1) Inclusive of compensation expense associated with time-vested and performance-based restricted stock awards. (2) Expense related to awards issued to directors is recognized as directors’ fees within other noninterest expense. The Company has standard form agreements used for stock option and restricted stock awards. The standard form agreements used for the Chief Executive Officer and all other Executive Officers have previously been disclosed in Securities and Exchange Commission filings and generally provide that: (1) any unvested options or unvested restricted stock vest upon a Change of Control; and, that (2) any stock options which vest pursuant to a Change of Control, which is an event described in Section 280G of the Internal Revenue Code of 1986, will be cashed out at the difference between the acquisition price and the exercise price of the stock option. Stock Options The fair value of each stock option grant is estimated on the date of the grant using the Black-Scholes option-pricing model with the following assumptions used for grants under the identified plans: • Expected volatility is based on the standard deviation of the historical volatility of the weekly adjusted closing price of the Company’s shares for a period equivalent to the expected life of the option. • Expected life represents the period of time that the option is expected to be outstanding, taking into account the contractual term, historical exercise/forfeiture behavior, and the vesting period, if any. • Expected dividend yield is an annualized rate calculated using the most recent dividend payment at time of grant and the Company’s average trailing twelve-month daily closing stock price. • The risk-free rate is based on the U.S. Treasury yield curve in effect at the time of grant for a period equivalent to the expected life of the option. • Effective January 1, 2017, the Company adopted new accounting guidance and elected to no longer estimate forfeitures on stock compensation and instead recognize forfeitures when they occur. The election required a cumulative effect adjustment to retained earnings which did not materially impact the Company's consolidated financial position. During the year ended December 31, 2019, there were no awards granted by the Company of nonqualified options to purchase shares of common stock. The following table presents the awards granted by the Company of nonqualified options to purchase shares of common stock for the periods presented: Years Ended December 31 2018 2017 Date of grant 4/3/2018 11/7/2017 Plan 2010 2010 Options granted 5,000 5,000 Vesting period (beginning on the grant date) 21 months 14 months Expiration date 4/3/2028 11/7/2027 Expected volatility 21.15 % 20.80 % Expected life (years) 5.5 5.5 Expected dividend yield 1.94 % 1.87 % Risk free interest rate 2.62 % 2.02 % Fair value per option $ 13.46 $ 12.43 Under all of the Company’s stock based plans, the option exercise price is based upon the average of the high and low trading value of the stock on the date of grant. Stock option awards granted to date under all plans expire at various dates through 2028 . The following table presents relevant information relating to the Company’s stock options for the periods presented: Years Ended December 31 2019 2018 2017 (Dollars in thousands, except per share data) Fair value of stock options vested based on grant date fair value $ 21 $ 85 $ 72 Intrinsic value of stock options exercised $ 883 $ 1,525 $ 1,082 Cash received from stock option exercises $ 396 $ 1,024 $ 918 Tax benefit realized on stock option exercises $ 248 $ 429 $ 442 Weighted average grant date fair value of options granted (per share) n/a $ 13.46 $ 12.43 The following table presents a summary of stock option award activity for the year ended December 31, 2019 . Outstanding Nonvested Stock Option Weighted Weighted Aggregate Stock Weighted (Dollars in thousands, except per share data) Balance at January 1, 2019 54,500 $ 37.28 3,332 $ 12.94 Granted — — — — Exercised (16,000 ) 24.76 n/a n/a Vested n/a n/a (1,666 ) 12.43 Forfeited — — — — Expired — — — — Balance at December 31, 2019 38,500 (2) $ 42.49 4.00 years $ 1,584 1,666 $ 13.46 Options outstanding and expected to vest at December 31, 2019 38,500 (3) $ 42.49 4.00 years $ 1,584 Options exercisable at December 31, 2019 36,834 (4) $ 41.21 3.81 years $ 1,563 Unrecognized compensation cost $ — Weighted average remaining recognition period (years) 0.00 (1) The aggregate intrinsic value represents the total pre-tax intrinsic value, based on the average of the high price and low price at which the Company’s common stock traded on December 31, 2019 of $83.64 , which would have been received by in-the-money option holders had they all exercised their options as of that date. (2) Inclusive of 22,500 stock options outstanding to Directors. (3) Inclusive of 22,500 vested stock options and expected to vest to Directors. (4) Inclusive of 20,834 vested stock options outstanding to Directors. Restricted Stock The Company grants both time-vested restricted stock awards as well as performance-based restricted stock awards. During the years ended December 31, 2019 , 2018 , and 2017 the Company made the following restricted stock award grants: Shares Granted Plan Fair Value (1) Vesting Period Time-vested 2019 2/21/2019 43,250 2005 $ 83.87 Ratably over 5 years from grant date 3/15/2019 600 2005 $ 79.55 Ratably over 5 years from grant date 4/1/2019 1,090 2005 $ 82.62 Ratably over 3 years from grant date 5/21/2019 6,500 2018 $ 77.08 Immediately upon grant date 2018 2/15/2018 39,950 2005 $ 71.75 Ratably over 5 years from grant date 2/27/2018 1,150 2005 $ 72.60 Ratably over 5 years from grant date 5/15/2018 530 2005 $ 74.00 Ratably over 5 years from grant date 5/22/2018 6,000 2018 $ 76.58 Immediately upon grant date 11/15/2018 560 2005 $ 77.78 Ratably over 5 years from grant date 2017 2/13/2017 1,200 2005 $ 62.53 Ratably over 5 years from grant date 2/16/2017 34,150 2005 $ 63.10 Ratably over 5 years from grant date 3/31/2017 500 2005 $ 65.63 Ratably over 5 years from grant date 4/3/2017 1,500 2005 $ 64.14 Once on November 30, 2017 (2) 5/15/2017 1,000 2005 $ 64.03 Ratably over 5 years from grant date 5/23/2017 7,000 2010 $ 61.95 At the end of 5 years from grant date (3) 6/15/2017 950 2005 $ 66.18 Ratably over 5 years from grant date Performance-based 2/21/2019 15,900 2005 $ 83.87 The earlier of: the date on which it is determined if the performance goal has been achieved; or, March 31, 2022. 2/15/2018 16,300 2005 $ 71.75 The earlier of: the date on which it is determined if the performance goal has been achieved; or, March 31, 2021. 2/16/2017 14,400 2005 $ 63.10 The earlier of: the date on which it is determined if the performance goal has been achieved; or, March 31, 2020. (1) The fair value of the restricted stock awards are based upon the average of the high and low prices at which the Company’s common stock traded on the date of grant. The holders of time-vested restricted stock awards participate fully in the rewards of stock ownership of the Company, including voting and dividend rights. The holders of performance-based restricted stock awards do not participate in the rewards of stock ownership of the Company until vested. The holders of all restricted stock awards are not required to pay any consideration to the Company for the awards. (2) This restricted stock grant fully vested upon an employee's termination, on November 30, 2017. (3) These restricted stock grants will vest at the end of a five year period, or earlier if the director ceases to be a director for any reason other than cause, such as, for example, by retirement. The following table presents the fair value of restricted stock awards vesting during the periods presented: Years Ended December 31 2019 2018 2017 (Dollars in thousands) Fair value of restricted stock awards upon vesting $ 6,005 $ 6,277 $ 5,717 The following table presents a summary of restricted stock award activity for the year ended December 31, 2019 : Outstanding Restricted Stock Weighted Average (Dollars in thousands, except per share data) Balance at January 1, 2019 202,106 $ 55.62 Granted 67,340 83.16 Vested/released (74,272 ) 49.56 Forfeited (1,390 ) 64.76 Balance at December 31, 2019 193,784 (1) $ 67.48 Unrecognized compensation cost (inclusive of directors’ fees) $ 8,098 Weighted average remaining recognition period (years) 2.99 (1) Inclusive of 17,925 restricted stock awards outstanding to Directors.

DERIVATIVES AND HEDGING ACTIVIT

DERIVATIVES AND HEDGING ACTIVITIES	12 Months Ended
	Dec. 31, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVES AND HEDGING ACTIVITIES	DERIVATIVES AND HEDGING ACTIVITIES The Company’s derivative financial instruments are used to manage differences in the amount, timing, and duration of the Company’s known or expected cash receipts and its known or expected cash payments principally to manage the Company’s interest rate risk. Additionally, the Company enters into interest rate derivatives and foreign exchange contracts to accommodate the business requirements of its customers ("customer related positions"). The Company minimizes the market and liquidity risks of customer related positions by entering into similar offsetting positions with broker-dealers. Derivative instruments are carried at fair value in the Company’s financial statements. The accounting for changes in the fair value of a derivative instrument is dependent upon whether or not it qualifies as a hedge for accounting purposes, and further, by the type of hedging relationship. The Company does not enter into proprietary trading positions for any derivatives. Interest Rate Positions The Company may utilize interest rate derivatives as hedging instruments against interest rate risk associated with the Company’s borrowings and loan portfolios. An interest derivative is an agreement whereby one party agrees to pay a floating rate of interest on a notional principal amount in exchange for receiving a fixed rate of interest on the same notional amount, for a predetermined period of time, from a second party. The amounts relating to the notional principal amount are not actually exchanged. The following table reflects information about the Company’s derivative positions as of the dates indicated below for interest rate swaps which qualify as cash flow hedges for accounting purposes: December 31, 2019 Weighted Average Rate Notional Amount Weighted Average Maturity Current Pay Fixed Fair Value (in thousands) (in years) (in thousands) Interest rate swaps on borrowings $ 75,000 2.18 1.90 % 1.53 % $ 140 Current Rate Paid Receive Fixed Swap Rate Interest rate swaps on loans 450,000 3.66 1.76 % 2.37 % 12,907 Current Rate Paid Receive Fixed Swap Rate Cap - Floor Interest rate collars on loans 400,000 3.66 1.76 % 2.73% - 2.20% 9,896 Total $ 925,000 $ 22,943 December 31, 2018 Weighted Average Rate Notional Amount Weighted Average Maturity Current Pay Fixed Fair Value (in thousands) (in years) (in thousands) Interest rate swaps on borrowings $ 75,000 3.18 2.74 % 1.53 % $ 2,282 Current Rate Paid Receive Fixed Swap Rate Interest rate swaps on loans 250,000 4.52 2.57 % 2.67 % 2,938 Current Rate Paid Receive Fixed Swap Rate Cap - Floor Interest rate collars on loans 250,000 4.17 2.47 % 3.02% - 2.51% 3,344 Total $ 575,000 $ 8,564 The maximum length of time over which the Company is currently hedging its exposure to the variability in future cash flows for forecasted transactions related to the payment of variable interest on existing financial instruments is 4.9 years. For derivative instruments that are designated and qualify as cash flow hedging instruments, the effective portion of the gains or losses is reported as a component of other comprehensive income ("OCI"), and is subsequently reclassified into earnings in the period that the hedged forecasted transaction affects earnings. The Company expects approximately $6.0 million (pre-tax) to be reclassified to interest income and $150,000 (pre-tax) to be reclassified as an offset to interest expense, from OCI related to the Company’s cash flow hedges in the next twelve months. This reclassification is due to anticipated payments that will be made and/or received on the swaps based upon the forward curve as of December 31, 2019 . The Company recognized net amortization income that was an offset to interest expense related to previously terminated swaps of $231,000 and $244,000 for the years ended December 31, 2018 and 2017 , respectively. The Company did not recognize any amortization income related to previously terminated swaps for the year ended December 31, 2019 . The Company had no fair value hedges during 2019 , 2018 and 2017 . Customer Related Positions Loan level derivatives, primarily interest rate swaps, offered to commercial borrowers through the Company’s loan level derivative program do not qualify as hedges for accounting purposes. The Company believes that its exposure to commercial customer derivatives is limited because these contracts are simultaneously matched at inception with an offsetting dealer transaction. Derivatives with dealer counterparties are then either cleared through a clearinghouse or settled directly with a single counterparty. The commercial customer derivative program allows the Company to retain variable-rate commercial loans while allowing the customer to synthetically fix the loan rate by entering into a variable-to-fixed interest rate swap. The amounts relating to the notional principal amount are not actually exchanged. Beginning in 2020, the Company will be subject to over-the-counter derivative clearing requirements, which require certain derivatives to be cleared through central clearing houses. Accordingly, the Company began to clear certain derivative transactions through the Chicago Mercantile Exchange Clearing House ("CME") in December of 2019. This clearing house requires the Company to post initial and variation margin to mitigate the risk of non-payment, the latter of which is received or paid daily based on the net asset or liability position of the contracts. Foreign exchange contracts offered to commercial borrowers through the Company’s derivative program do not qualify as hedges for accounting purposes. The Company acts as a seller and buyer of foreign exchange contracts to accommodate its customers. To mitigate the market and liquidity risk associated with these derivatives, the Company enters into similar offsetting positions. The amounts relating to the notional principal amount are exchanged. The following table reflects the Company’s customer related derivative positions as of the dates indicated below for those derivatives not designated as hedging: Number of Notional Amount Maturing Less than 1 year Less than 2 years Less than 3 years Less than 4 years Thereafter Total Fair Value December 31, 2019 (Dollars in thousands) Loan level swaps Receive fixed, pay variable 299 $ 156,690 $ 125,203 $ 85,603 $ 165,599 $ 1,044,315 $ 1,577,410 $ 48,596 Pay fixed, receive variable 290 $ 156,690 $ 125,203 $ 85,603 $ 165,599 $ 1,044,315 $ 1,577,410 $ (48,591 ) Foreign exchange contracts Buys foreign currency, sells U.S. currency 40 $ 91,434 $ — $ — $ — $ — $ 91,434 $ (81 ) Buys U.S. currency, sells foreign currency 40 $ 91,434 $ — $ — $ — $ — $ 91,434 $ 123 December 31, 2018 (Dollars in thousands) Loan level swaps Receive fixed, pay variable 235 $ 50,702 $ 124,222 $ 97,904 $ 47,308 $ 631,471 $ 951,607 $ (2,907 ) Pay fixed, receive variable 220 $ 50,702 $ 124,222 $ 97,904 $ 47,308 $ 631,471 $ 951,607 $ 2,903 Foreign exchange contracts Buys foreign currency, sells U.S. currency 27 $ 60,297 $ 3,505 $ — $ — $ — $ 63,802 $ (1,404 ) Buys U.S. currency, sells foreign currency 27 $ 60,297 $ 3,505 $ — $ — $ — $ 63,802 $ 1,434 (1) The Company may enter into one dealer swap agreement which offsets multiple commercial borrower swap agreements. Mortgage Derivatives The Company enters into commitments to fund residential mortgage loans at specified rates and times in the future, with the intention that loans will likely be sold subsequently in the secondary market. Mortgage loan commitments are referred to as derivative loan commitments if the loan that will result from exercise of the commitment will be held for sale upon funding. These commitments are recognized at fair value on the consolidated balance sheet in other assets and other liabilities with changes in their fair values recorded within mortgage banking income. In addition, the Company has elected the fair value option to carry loans held for sale at fair value. The change in fair value of loans held for sale is recorded in current period earnings as a component of mortgage banking income in accordance with the Company's fair value election. The change in fair value associated with loans held for sale was an increase of $822,000 , a decrease of $51,000 and a decrease of $113,000 for the years ended December 31, 2019 , 2018 and 2017 , respectively. These amounts were offset in earnings by the change in the fair value of mortgage derivatives. Outstanding loan commitments expose the Company to the risk that the price of the loans arising from exercise of the loan commitment might change from inception of the rate lock to funding of the loan due to changes in mortgage interest rates. If interest rates increase, the value of these loan commitments decreases. Conversely, if interest rates decrease, the value of these loan commitments increases. To protect against the price risk inherent in derivative loan commitments, the Company utilizes both "mandatory delivery" and "best efforts" forward loan sale commitments to mitigate the risk of potential decreases in the values of loans that would result from the exercise of the derivative loan commitments. Mandatory delivery contracts are accounted for as derivative instruments. Included in the mandatory delivery forward commitments are To Be Announced securities ("TBAs"). Certain assumptions, including pull through rates and rate lock periods, are used in managing the existing and future hedges. The accuracy of underlying assumptions will impact the ultimate effectiveness of any hedging strategies. With mandatory delivery contracts, the Company commits to deliver a certain principal amount of mortgage loans to an investor at a specified price on or before a specified date. If the Company fails to deliver the amount of mortgages necessary to fulfill the commitment by the specified date, it is obligated to pay a "pair-off" fee, based on then-current market prices, to the investor/counterparty to compensate the investor for the shortfall. Generally the Company makes this type of commitment once mortgage loans have been funded and are held for sale, in order to minimize the risk of failure to deliver the requisite volume of loans to the investor and paying pair-off fees as a result. The Company also sells TBA securities to offset potential changes in the fair value of derivative loan commitments. Generally the Company sells TBA securities by entering into derivative loan commitments for settlement in 30 to 90 days. The Company expects that mandatory delivery contracts, including TBA securities, will experience changes in fair value opposite to the changes in the fair value of derivative loan commitments. With best effort contracts, the Company commits to deliver an individual mortgage loan of a specified principal amount and quality to an investor if the loan to the underlying borrower closes. Generally best efforts cash contracts have no pair off risk regardless of market movement. The price the investor will pay the seller for an individual loan is specified prior to the loan being funded (e.g., on the same day the lender commits to lend funds to a potential borrower). The Company expects that these best efforts forward loan sale commitments will experience a net neutral shift in fair value with related derivative loan commitments. The aggregate amount of net realized gains or losses on sales of loans included within mortgage banking income was $13.2 million , $3.6 million and $4.7 million for the years ended December 31, 2019 , 2018 and 2017 , respectively. The table below presents the fair value of the Company’s derivative financial instruments, as well as their classification on the balance sheet at the dates indicated: Asset Derivatives (1) Liability Derivatives (2) Fair Value at Fair Value at Fair Value at Fair Value at December 31, 2019 December 31, 2018 December 31, 2019 December 31, 2018 (Dollars in thousands) Derivatives designated as hedges Interest rate derivatives $ 23,140 $ 8,955 $ 197 $ 391 Derivatives not designated as hedges Customer Related Positions: Loan level derivatives 52,374 15,580 52,369 15,584 Foreign exchange contracts 1,191 1,578 1,149 1,548 Mortgage Derivatives Interest rate lock commitments 1,680 91 — — Forward sale loan commitments — 106 12 — Forward sale hedge commitments — — 196 — 55,245 17,355 53,726 17,132 Total $ 78,385 $ 26,310 $ 53,923 $ 17,523 (1) All asset derivatives are located in other assets on the balance sheet. (2) All liability derivatives are located in other liabilities on the balance sheet. The table below presents the effect of the Company’s derivative financial instruments included in OCI and current earnings for the periods indicated: Years Ended December 31 2019 2018 2017 (Dollars in thousands) Derivatives designated as hedges Gain in OCI on derivatives (effective portion), net of tax $ 10,331 $ 4,829 $ 443 Gain (loss) reclassified from OCI into interest income or interest expense (effective portion) $ 2,346 $ 1,000 $ (441 ) Loss recognized in income on derivatives (ineffective portion and amount excluded from effectiveness testing) Interest expense $ — $ — $ — Other expense — — — Total $ — $ — $ — Derivatives not designated as hedges Changes in fair value of customer related positions Other income $ 39 $ 46 $ 6 Other expenses (18 ) (29 ) (21 ) Changes in fair value of mortgage derivatives Mortgage banking income 1,275 39 (39 ) Total $ 1,296 $ 56 $ (54 ) The Company's derivative agreements with institutional counterparties contain various credit-risk related contingent provisions, such as requiring the Company to maintain a well-capitalized capital position. If the Company fails to meet these conditions, the counterparties could request the Company make immediate payment or demand that the Company provide immediate and ongoing full collateralization on derivative positions in net liability positions. The aggregate fair value of all derivative instruments with credit-risk related contingent features that were in a net liability position was $26.0 million and $176,000 at December 31, 2019 and December 31, 2018 , respectively. Although none of the contingency provisions have applied as of December 31, 2019 and December 31, 2018 , the Company has posted collateral to offset the net liability exposure with institutional counterparties. Additionally, for cleared derivatives the CME requires that the Company to post initial and variation margin to mitigate the risk of non-payment, which amounted to $ 1.3 million at December 31, 2019. By using derivatives, the Company is exposed to credit risk to the extent that counterparties to the derivative contracts do not perform as required. Should a counterparty fail to perform under the terms of a derivative contract, the Company’s credit exposure on interest rate swaps is limited to the net positive fair value and accrued interest of all swaps with each counterparty. The Company seeks to minimize counterparty credit risk through credit approvals, limits, monitoring procedures, and obtaining collateral, where appropriate. Institutional counterparties must have an investment grade credit rating and be approved by the Company’s Board of Directors. In addition, certain derivative contracts executed bilaterally with a dealer counterparty in the over-the-counter market are cleared through a clearinghouse, whereby the clearinghouse becomes the counterparty to the transaction. As such, management believes the risk of incurring credit losses on derivative contracts with those counterparties is remote. The Company's exposure relating to institutional counterparties was $25.4 million and $18.4 million at December 31, 2019 and 2018 , respectively. The Company’s exposure relating to customer counterparties was approximately $51.0 million and $6.4 million at December 31, 2019 and 2018

BALANCE SHEET OFFSETTING

BALANCE SHEET OFFSETTING	12 Months Ended
	Dec. 31, 2019
Offsetting [Abstract]
Balance Sheet Offsetting Disclosure [Text Block]	BALANCE SHEET OFFSETTING The Company does not offset fair value amounts recognized for derivative instruments or repurchase agreements. The Company does net the amount recognized for the right to reclaim cash collateral against the obligation to return cash collateral arising from derivative instruments executed with the same counterparty under a master netting arrangement. Collateral legally required to be maintained at dealer banks by the Company is monitored and adjusted as necessary. The following tables present the Company's asset and liability derivative positions and the potential effect of netting arrangements on its financial position, as of the dates indicated: Gross Amounts Not Offset in the Statement of Financial Position Gross Amounts Recognized in the Statement of Financial Position Gross Amounts Offset in the Statement of Financial Position Net Amounts Presented in the Statement of Financial Position Financial Instruments (1) Collateral Pledged (Received) Net Amount December 31, 2019 (Dollars in thousands) Derivative Assets Interest rate swaps $ 23,140 $ — $ 23,140 $ 23,140 $ — $ — Loan level derivatives 52,374 — 52,374 1,742 — 50,632 Customer foreign exchange contracts 1,191 — 1,191 — — 1,191 $ 76,705 $ — $ 76,705 $ 24,882 $ — $ 51,823 Derivative Liabilities Interest rate swaps $ 197 $ — $ 197 $ — $ 197 $ — Loan level derivatives 52,369 — 52,369 24,882 25,296 2,191 Customer foreign exchange contracts 1,149 — 1,149 — — 1,149 $ 53,715 $ — $ 53,715 $ 24,882 $ 25,493 $ 3,340 (1) Reflects offsetting derivative positions with the same counterparty. Gross Amounts Not Offset in the Statement of Financial Position Gross Amounts Recognized in the Statement of Financial Position Gross Amounts Offset in the Statement of Financial Position Net Amounts Presented in the Statement of Financial Position Financial Instruments (1) Collateral Pledged (Received) Net Amount December 31, 2018 (Dollars in thousands) Derivative Assets Interest rate swaps $ 8,955 $ — $ 8,955 $ 391 $ (5,527 ) $ 3,037 Loan level derivatives 15,580 — 15,580 6,165 (3,001 ) 6,414 Customer foreign exchange contracts 1,578 — 1,578 — — 1,578 $ 26,113 $ — $ 26,113 $ 6,556 $ (8,528 ) $ 11,029 Derivative Liabilities Interest rate swaps $ 391 $ — $ 391 $ 391 $ — $ — Loan level derivatives 15,584 — 15,584 6,165 173 9,246 Customer foreign exchange contracts 1,548 — 1,548 — — 1,548 $ 17,523 $ — $ 17,523 $ 6,556 $ 173 $ 10,794 (1)

INCOME TAXES

INCOME TAXES	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES The provision for income taxes is comprised of the following components: Years Ended December 31 2019 2018 2017 (Dollars in thousands) Current expense Federal $ 27,980 $ 25,129 $ 28,852 State 14,359 13,672 9,278 Total current expense 42,339 38,801 38,130 Deferred expense (benefit) Federal 9,080 (3,080 ) 7,953 State 1,514 (1,417 ) 1,258 Total deferred expense (benefit) 10,594 (4,497 ) 9,211 Total expense $ 52,933 $ 34,304 $ 47,341 The difference between the statutory federal income tax rate and the effective income tax rate reported for the last three years is detailed below: Years Ended December 31 2019 2018 2017 (Dollars in thousands) Computed statutory federal income tax provision $ 45,803 21.00 % $ 32,744 21.00 % $ 47,091 35.00 % State taxes, net of federal tax benefit 12,262 5.63 % 9,633 6.18 % 6,817 5.07 % Merger and other related costs (non-deductible) 582 0.27 % 130 0.08 % 213 0.16 % Change in valuation allowance 17 0.01 % 49 0.03 % 31 0.02 % Revaluation of net deferred tax assets — — % — — % 1,895 1.41 % New Markets Tax Credits (2,675 ) (1.23 )% (3,960 ) (2.54 )% (3,960 ) (2.94 )% Increase in cash surrender value of life insurance (1,144 ) (0.52 )% (1,160 ) (0.74 )% (1,445 ) (1.07 )% Low Income Housing Project Investments (1,696 ) (0.78 )% (1,030 ) (0.66 )% (1,253 ) (0.93 )% Stock-based compensation (824 ) (0.38 )% (885 ) (0.57 )% (1,258 ) (0.94 )% Nontaxable interest, net (757 ) (0.35 )% (566 ) (0.36 )% (987 ) (0.73 )% Other, net 1,365 0.63 % (651 ) (0.42 )% 197 0.15 % Total expense $ 52,933 24.28 % $ 34,304 22.00 % $ 47,341 35.20 % On December 22, 2017, the Tax Act was signed into law, reducing the corporate income tax rate from 35% to 21%. At December 31, 2017, the Company had not completed its accounting for the tax effect of enactment of the Tax Act; however, it made a reasonable estimate of the effects on its existing deferred tax balances. As a result of this rate reduction, the Company remeasured certain deferred tax assets and liabilities at December 31, 2017 based on the rates at which they are expected to reverse in the future, which is generally 21% for federal tax purposes. This remeasurement of deferred tax assets and liabilities resulted in a provisional amount recorded of $1.9 million . Also at December 31, 2017, the Company had recognized a provisional estimate of $466,000 to reassess the value of its low income housing projects investments ("LIHTC investments"). As of December 31, 2018, the Company completed its accounting for all of the enactment-date income tax effects of the Tax Act. The Company's tax expense for the year ended December 31, 2018 included an increase of $71,000 related to the provisional estimate recorded on the remeasurement of deferred tax asset and liabilities in 2017, mainly attributable to remeasurement of temporary differences. There was no change to this provisional amount recorded in 2017 related to the Company's LIHTC investments. The tax-effected components of the net deferred tax asset at December 31 of the years presented were as follows: 2019 2018 (Dollars in thousands) Deferred tax assets Accrued expenses not deducted for tax purposes $ 13,855 $ 11,922 Allowance for loan losses 18,993 17,764 Employee and director equity compensation 1,708 1,636 Loan basis difference fair value adjustment 6,804 4,761 Net operating loss carry-forward 2,546 170 Net unrealized loss on securities available for sale — 1,850 Operating lease liability 16,393 — Other 1,311 1,561 Gross deferred tax assets $ 61,610 $ 39,664 Valuation allowance (187 ) (170 ) Total deferred tax assets net of valuation allowance $ 61,423 $ 39,494 Deferred tax liabilities Core deposit and other intangibles $ 5,802 $ 3,803 Deferred loan fees, net 4,944 4,759 Derivatives fair value adjustment 6,461 2,413 Fixed assets 8,194 5,259 Goodwill 10,645 10,388 Prepaid pension 3,487 3,483 Right of use asset 15,911 — Other 3,965 1,139 Gross deferred tax liabilities $ 59,409 $ 31,244 Total net deferred tax asset $ 2,014 $ 8,250 Deferred tax assets are to be reduced by a valuation allowance if, based on the weight of available evidence, it is more likely than not that some portion or all of the deferred tax assets will not be realized. The realization of the tax benefit depends upon the existence of sufficient taxable income in future periods. The Company believes that it is more likely than not that its deferred tax assets as of December 31, 2019 , excluding the deferred tax asset on certain state net operating losses, will be realized through future reversals of existing taxable temporary differences and by offsetting other future taxable income. The Company believes it is more likely than not that the deferred tax asset related to certain state net operating losses generated from the Company's investments in low income housing partnerships, which expire over a 20-year period, will not be realized and has recorded a valuation allowance of $187,000 at December 31, 2019 , attributable to this deferred tax asset. The Company has a federal operating loss carry forward of $11.2 million acquired from a recent acquisition that is subject to annual change in ownership limitations under Internal Revenue Code Sec. 382 as of December 31, 2019 . The Company does not have a general business credit carry forward subject to expiration as of December 31, 2019 . Uncertainty in Income Taxes The Company and its subsidiaries file income tax returns in the U.S. federal jurisdiction as well as in various states. The Company is subject to U.S. federal, state and local income tax examinations by tax authorities for the 2016 through 2018 tax years including any related income tax filings from its recent acquisitions. The Company believes that its income tax returns have been filed based upon applicable statutes, regulations and case law in effect at the time of filing, however, the Internal Revenue Service ("IRS") and /or state jurisdictions could disagree with the Company's interpretation upon examination. The Company accounts for uncertainties in income taxes by providing a tax reserve for certain positions. The following is a reconciliation of the beginning and ending amount of unrecognized tax benefits: (Dollars in thousands) Balance at December 31, 2017 $ 142 Increase for current year tax positions 73 Balance at December 31, 2018 215 Reduction of tax positions for prior years (127 ) Increase for current year tax positions 444 Balance at December 31, 2019 $ 532 Increases to the Company's unrealized tax positions occur as a result of accruing for the unrecognized tax benefit as well the accrual of interest and penalties related to prior year positions. Decreases in the Company's unrealized tax positions occur as a result of the statute of limitation lapsing on prior year positions and/or settlements relating to outstanding positions. The table above does not include the indirect federal benefit of state tax positions of approximately $116,000 . All of the Company’s unrecognized tax benefits, including the indirect federal benefit of state tax positions, are recorded as a component of income tax expense. During the year ended December 31, 2019 , the Company recognized a benefit of approximately $10,000 , and during the years ended December 31, 2018 and 2017 recognized expense of $24,000 and $18,000 , respectively, in the provision for income taxes for interest and penalties related to uncertain tax positions. Accordingly, the Company has accrued approximately $43,000 , $53,000 and $29,000 for the payment of interest and penalties as of December 31, 2019 , 2018 and 2017

LOW INCOME HOUSING PROJECT INVE

LOW INCOME HOUSING PROJECT INVESTMENTS Low Income Housing Project Investments	12 Months Ended
	Dec. 31, 2019
Low Income Housing Project Investments [Abstract]
Investments in Low Income Housing Projects [Text Block]	LOW INCOME HOUSING PROJECT INVESTMENTS The Company has invested in low income housing projects that generate Low Income Housing Tax Credits ("LIHTC") which provide the Company with tax credits and operating loss tax benefits over a period of approximately 15 years. None of the original investment is expected to be repaid. The following table presents certain information related to the Company's investments in low income housing projects as of December 31 of the years presented: 2019 2018 2017 (Dollars in thousands) Original investment value $ 96,275 $ 50,232 $ 47,399 Current recorded investment $ 72,510 $ 33,681 $ 35,225 Unfunded liability obligation $ 34,967 $ 3,935 $ 4,536 Tax credits and benefits earned during the year $ 7,342 $ 5,407 $ 5,654 Amortization of investments during the year (1) $ 5,645 $ 4,377 $ 4,402 Net income tax benefit recognized during the year $ 1,696 $ 1,030 $ 1,253 (1) The 2017 amount is inclusive of $466,000 related to the revaluation of Low Income Housing tax credit investments as a result of the 2017 Tax Act.

EMPLOYEE BENEFIT PLANS

EMPLOYEE BENEFIT PLANS	12 Months Ended
	Dec. 31, 2019
Retirement Benefits [Abstract]
EMPLOYEE BENEFIT PLANS	EMPLOYEE BENEFIT PLANS Pension The Company maintains a multiemployer defined benefit pension plan (the "Pension Plan") administered by Pentegra Retirement Services (the "Fund" or "Pentegra Defined Benefit Plan for Financial Institutions"). The Fund does not segregate the assets or liabilities of all participating employers and accordingly, disclosure of plan assets, accumulated vested and nonvested benefits is not possible. Effective July 1, 2006, the Company froze the defined benefit plan by eliminating all future benefit accruals. In conjunction with the acquisition of Peoples Federal Bancshares, Inc., the parent of Peoples Federal Savings Bank ("Peoples") in 2015, the Company acquired the Peoples Federal Defined Benefit Pension Plan ("Peoples Plan"). The Peoples Plan was frozen at the date of acquisition and will be maintained in the same manner as the Pension Plan. The Peoples Plan is also administered by Pentegra Retirement Services under the same Fund as the Pension Plan. The Company’s participation in the Pension Plan and the Peoples Plan (the "Pension Plans") for the annual period ended December 31, 2019 , is outlined in the table below. The "EIN/Pension Plan Number" column provides the Employer Identification Number ("EIN") and the three-digit plan number. The funding status of the Pension Plans is determined on the basis of the financial statements provided by the Fund using total plan assets and accumulated benefit obligation. The "FIP/RP Status Pending/Implemented" column indicates plans for which a financial improvement plan ("FIP") or a rehabilitation plan ("RP") is either pending or has been implemented. The "Expiration Date of Collective-Bargaining Agreement" column lists the expiration dates of any collective-bargaining agreement(s) to which the Pension Plans are subject. Financial information for the Fund is made available through the public Form 5500 which is available by April 15 th of the year following the plan year end. Funding Status FIP/RP Status Surcharge Expiration Minimum EIN/Pension 2019 2018 Pentegra defined benefit plan for financial institutions 13-5645888/333 At least 80 percent At least 80 percent No No N/A $ — Contributions to the Fund are based on each individual employer’s experience. The Company bears the market risk relating to the Pension Plan and will continue to fund the Pension Plan as required. The Pension Plan year is July 1 st through June 30 th . The Company’s total contributions to the Pension Plan did not represent more than 5% of the total contributions to the Pension Plan as indicated in the Pension Plan’s most recently available annual report dated June 30, 2019 . The comparability of employer contributions is impacted by asset performance, discount rates and the reduction in the number of covered employees year over year. The Company’s contributions to the Pension Plans were as follows for the periods indicated: Required Contributions - Plan Year Allocation Cash Payment Future period funding 2019-2020 2018-2019 2017-2018 (Dollars in thousands) 2019 $ 2,063 $ — $ 2,063 $ — $ — 2018 $ 2,642 $ 2,000 $ — $ 642 $ — 2017 $ 6,432 $ 5,000 $ — $ — $ 1,432 In conjunction with the acquisition of BHB in 2019, the Company acquired the Savings Banks Employees Retirement Association Pension Plan as adopted by BHB (the "BHB Plan"). The BHB Plan is administered by Savings Banks Employees Retirement Association (SBERA) and was frozen on October 31, 2014. Accumulated benefits for participants earned through the end of October 2014 remain secured by the BHB Plan assets as of December 31, 2019. Information pertaining to the BHB Plan at December 31, 2019 is as follows: Amount (Dollars in thousands) Change in plan assets: Fair value of plan assets at beginning of year $ 9,697 Actual return on plan assets 1,886 Employer contribution 505 Benefits paid (435 ) Fair value of plan assets at end of year $ 11,653 Change in benefit obligation: Benefit obligation at beginning of year 10,824 Interest cost 424 Actuarial loss 2,874 Benefits paid (435 ) Benefit obligation at end of year $ 13,687 Funded status and accrued liability at end of year $ (2,034 ) Accumulated benefit obligation at end of year $ 13,687 At December 31, 2019 the discount rate used to determine the benefit obligation was 3.11% . The components of net period pension cost are as follows for the year ended December 31, 2019: Amount (Dollars in thousands) Interest cost $ 424 Expected return on plan assets (780 ) Amortization of net actuarial loss 327 Net period pension benefit $ (29 ) The discount rate used to determine net periodic pension cost for the year ended December 31, 2019 was 4.03% and the expected long-term rate of return on plan assets used was 8.00% . Assumptions with respect to the expected long-term rate of return are based on prevailing yields on high-quality, fixed-income investments increased by a premium for equity return expectations. SBERA offers a common and collective trust as the underlying investment structure for pension plans participating in SBERA. The target allocation mix for the common and collective trust portfolio calls for an equity-based investment range from 43% to 57% of total portfolio assets. The remainder of the portfolio is allocated to fixed income securities with a target range of 15% to 25% and other investments including global asset allocation and hedge funds from 15% to 31% . The Trustees of SBERA, through the Association's Investment Committee, select investment managers for the common and collective trust portfolio. A professional investment advisory firm is retained by the Investment Committee to provide allocation analysis, performance measurement and to assist with manager searches. The overall investment objective is to diversify equity investments across a spectrum of investment types to limit risks from large market swings. The fair value of major categories of the BHB Plan assets as of December 31, 2019 are summarized below: Fair Value Measurements at Reporting Date Using Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) (Dollars in thousands) Collective funds $ 967 967 $ — $ — Equity securities 1,131 1,131 — — Mutual funds 3,628 3,628 — — Total investments in the fair value hierarchy $ 5,726 $ 5,726 $ — $ — Investments measured at net asset value (1) 5,927 $ 11,653 (1) Under the Fair Value Measurements and Disclosure Topic of the FASB ASC, certain investments that were measured at fair value at net asset value per share (or its equivalent) have not been classified in the fair value hierarchy. There were no transfers to or from Level 1, 2 and 3 during the period. The fair value hierarchy above was received from SBERA, the plan administrator. The BHB Plan assets measured at fair value in Level 1 are based on quoted market prices in an active exchange market. BHB Plan assets measured at fair value in Level 2 are based on pricing models that consider standard input factors such as observable market data, benchmark yields, interest rate volatilities, broker/dealer quotes, credit spreads and new issue data. BHB Plan assets measured at fair value in Level 3 are based on unobservable inputs, which include the SBERA’s assumptions and the best information available under the circumstance. Estimated future benefit payments for the BHB Plan are presented below: Amount (Dollars in thousands) 2020 $ 629 2021 $ 834 2022 $ 591 2023 $ 583 2024 $ 556 2025-2029 $ 2,867 The Company’s total defined benefit plan expense was $1.4 million , $1.1 million , and $1.9 million , for the years ending December 31, 2019 , 2018 , and 2017 , respectively. Additionally, in conjunction with the acquisition of Island Bancorp in 2017, the Company acquired the Edgartown National Bank Employee’s Retirement Plan. This pension plan was frozen at the date of acquisition and was subsequently dissolved. Postretirement Benefit Plans Employees retiring from the Bank after attaining age 65 , who have rendered at least 10 years of continuous full time service with Rockland Trust are entitled to a fixed contribution toward the premium for postretirement health care benefits and a $5,000 benefit paid upon death. The health care benefits are subject to deductibles, co-payment provisions and other limitations. The Bank may amend or change these benefits periodically. Additionally, the Company has acquired small postretirement plans and/or agreements in conjunction with various acquisitions. The expense related to these plans for the years ending December 31, 2019 , 2018 , and 2017 was not material. Supplemental Executive Retirement Plans The Bank maintains frozen defined benefit supplemental executive retirement plans ("SERP") for certain highly compensated employees designed to offset the impact of regulatory limits on benefits under qualified pension plans. The Bank also maintains defined benefit SERPs acquired from previous acquisitions. The Bank has established and funded rabbi trusts to accumulate funds in order to satisfy the contractual liability of these supplemental retirement plan benefits. These agreements provide for the Bank to pay all benefits from its general assets, and the establishment of these trust funds does not reduce nor otherwise affect the Bank’s continuing liability to pay benefits from such assets except that the Bank’s liability shall be offset by actual benefit payments made from the trusts. The related trust assets included in the Company's available for sale securities portfolio totaled $18.3 million and $16.6 million at December 31, 2019 and 2018 , respectively. The following table shows the defined benefit supplemental retirement expense, and the contributions paid to the plans which were used only to pay the current year benefits as of the dates indicated: 2019 2018 2017 (Dollars in thousands) Retirement expense $ 1,356 $ 1,683 $ 1,580 Contributions paid $ 486 $ 434 $ 367 Expected future benefit payments for the defined benefit supplemental executive retirement plans are presented below: Defined Benefit Supplemental Executive (Dollars in thousands) 2020 $ 472 2021 $ 466 2022 $ 458 2023 $ 571 2024 $ 1,220 2025-2029 $ 5,853 The measurement date used to determine the defined benefit supplemental executive retirement plans' benefits is December 31 for each of the years reported. The following table illustrates the status of the defined benefit supplemental executive retirement plans at December 31 for the years presented: Defined Benefit Supplemental Executive 2019 2018 2017 (Dollars in thousands) Change in accumulated benefit obligation Benefit obligation at beginning of year $ 14,963 $ 15,749 $ 14,177 Service cost 433 459 423 Interest cost 601 533 547 Actuarial loss (gain) 1,850 (1,344 ) 969 Benefits paid (486 ) (434 ) (367 ) Benefit obligation at end of year $ 17,361 $ 14,963 $ 15,749 Change in plan assets Fair value of plan assets at beginning of year $ — $ — $ — Employer contribution 486 434 367 Benefits paid (486 ) (434 ) (367 ) Fair value of plan assets at end of year $ — $ — $ — Funded status at end of year $ (17,361 ) $ (14,963 ) $ (15,749 ) Assets — — — Liabilities (17,361 ) (14,963 ) (15,749 ) Funded status at end of year $ (17,361 ) $ (14,963 ) $ (15,749 ) Amounts recognized in accumulated other comprehensive income ("AOCI") Net loss $ 3,509 $ 1,705 $ 3,465 Prior service cost 494 770 1,047 Amounts recognized in AOCI $ 4,003 $ 2,475 $ 4,512 Information for plans with an accumulated benefit obligation in excess of plan assets Projected benefit obligation $ 17,361 $ 14,963 $ 15,749 Accumulated benefit obligation $ 17,361 $ 14,963 $ 15,749 Net periodic benefit cost Service cost $ 433 $ 459 $ 423 Interest cost 601 533 547 Amortization of prior service cost 276 276 276 Recognized net actuarial loss 46 415 334 Net periodic benefit cost $ 1,356 $ 1,683 $ 1,580 Amounts in accumulated other comprehensive income expected to be recognized in net periodic benefit cost over next fiscal year Net actuarial loss $ 471 $ 41 $ 415 Net prior service cost $ 276 $ 276 $ 276 Discount rate used for benefit obligation 2.00 - 3.04% 3.24 - 4.09% 2.48-3.45% Discount rate used for net periodic benefit cost 3.24 - 4.09% 2.48 - 3.45% 2.49-3.94% Rate of compensation increase n/a n/a n/a Other Employee Benefits The Bank may choose to create an incentive compensation plan for senior management and other officers to participate in at varying levels. In addition, the Bank may also pay a discretionary bonus to senior management, officers, and/or non-officers of the Bank. The expense for the incentive plans and the discretionary bonus amounted to $16.3 million , $13.8 million and $10.9 million in 2019 , 2018 and 2017 , respectively. The Bank has an Employee Savings Plan that qualifies as a deferred salary arrangement under Section 401(k) of the Internal Revenue Code. Under the Employee Savings Plan, participating employees may defer a portion of their earnings, not to exceed the Internal Revenue Service annual contribution limits. The Bank matches 25% of each employee’s contributions up to the first 6% of the employee’s eligible earnings. The 401(k) Plan incorporates an Employee Stock Ownership Plan for contributions invested in the Company’s common stock. The Company also provides three defined contributions under this Plan, providing the employees are deemed eligible. To be eligible for these contributions, an employee must complete one year and 1,000 hours of service. The defined contributions are made up of a safe harbor contribution, in which eligible employees receive a 3% cash contribution of eligible earnings to the social security limit, a discretionary contribution in which eligible employees receive a 2% cash contribution of eligible earnings up to the social security limit and a 5% cash contribution of eligible earnings over the social security limit up to the maximum amount permitted by law. Benefits contributed to employees under this defined contribution plan vest immediately. The defined contribution plan expense was $6.6 million , $5.4 million and $5.0 million for the years ended December 2019 , 2018 and 2017 , respectively. The Company has a non-qualified deferred compensation plan which allows for deferrals of base salary and incentive payments until an elected distribution date in the future. This deferred compensation plan is available to certain highly compensated employees. Deferrals are invested at the election of the participant into one of the actively managed funds made available to the participant through the Company's Investment Management Group. The funds are held in a rabbi trust until the elected date of distribution. The Company has a non-qualified 401(k) Restoration Plan ("Restoration Plan") for certain executive officers. The Restoration Plan is intended to contribute to each participant the amount of matching and discretionary contributions which would have been made to the existing Rockland Trust 401(k) plan on the participant's behalf, but were prohibited due to Internal Revenue Code limitations. Deferrals are invested at the election of the participant into one of the actively managed funds made available to the participant through the Company's Investment Management Group or in the Company's stock. These funds are held in a rabbi trust until the elected date of distribution. The Company recognized expense of $356,000 , $278,000 and $267,000 related to this plan for services performed for the years ended December 31, 2019 , 2018 and 2017 , respectively. Also as part of the Peoples acquisition in 2015, the Company assumed various Salary Continuation Agreements with certain current and former senior executives. The agreements require the payment of specified benefits upon retirement over periods of ten or twenty years as described in each agreement. Expense related to the Salary Continuation Agreements was $295,000 , $287,000 and $279,000 for the years ended December 31, 2019 , 2018 and 2017 , respectively. The Company also assumed a Peoples supplemental retirement plan with a former executive, whereby the amounts paid under this plan commenced upon the executive's retirement and continue until 2026. The expense related to the supplemental retirement plan for the years ended December 31, 2019 , 2018 and 2017 was not material. Additionally, in conjunction with the acquisition of BHB in 2019, the Company assumed an Employee Stock Ownership Plan and a 401(k) retirement plan. These plans will be terminated by the Company subsequent to December 31, 2019. Director Benefits The Company maintains two deferred compensation plans for the Company’s Board of Directors which permit non-employee directors to defer cash fees, one which was in effect through December 31, 2018 and a new plan which was adopted effective January 1, 2019. Under the plan in effect through December 31, 2018, deferred compensation is invested in Company stock and held by the Company's Investment Management Group. Under the plan that took effect January 1, 2019, participating directors may defer all or a portion of their cash compensation into a choice of diversified investment portfolios comprised of stocks, bonds and cash. The amount of compensation deferred during 2019 , 2018 , and 2017 was $142,000 , $142,000 , and $143,000 , respectively. As a result of the Peoples acquisition during 2015, the Company assumed several Director Retirement Agreements. The agreements require the payment of specified benefits upon retirement over periods of ten or twenty years as described in each agreement. The expense related to the Director Retirement Agreements for the years ended December 31, 2019 , 2018 and 2017

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	FAIR VALUE MEASUREMENTS Fair value is a market-based measure considered from the perspective of a market participant rather than an entity-specific measure. Therefore, even when market assumptions are not readily available, the Company’s own assumptions are set to reflect those that market participants would use in pricing the asset or liability at the measurement date. If there has been a significant decrease in the volume and level of activity for the asset or liability, regardless of the valuation technique(s) used, the objective of a fair value measurement remains the same. Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction (that is, not a forced liquidation or distressed sale) between market participants at the measurement date under current market conditions. The Company uses prices and inputs that are current as of the measurement date. In periods of market dislocation, the observability of prices and inputs may be reduced for many instruments. This condition could cause an instrument to be reclassified from one level to another. The Fair Value Measurements and Disclosures Topic of the FASB ASC defines fair value and establishes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy under the Fair Value Measurements and Disclosures Topic of the FASB ASC are described below: Level 1 – Inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date. Level 2 – Valuations based on quoted prices in markets that are not active or for which all significant inputs are observable, either directly or indirectly. Level 3 – Prices or valuations that require inputs that are both significant to the fair value measurement and unobservable. To the extent that valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. Valuation Techniques There have been no changes in the valuation techniques used during the current period. Securities: Trading and Equity Securities These equity securities are valued based on market quoted prices. These securities are categorized in Level 1 as they are actively traded and no valuation adjustments have been applied. U.S. Government Agency Securities Fair value is estimated using either multi-dimensional spread tables or benchmarks. The inputs used include benchmark yields, reported trades, and broker/dealer quotes. These securities are classified as Level 2. Agency Mortgage-Backed Securities Fair value is estimated using either a matrix or benchmarks. The inputs used include benchmark yields, reported trades, broker/dealer quotes, and issuer spreads. These securities are categorized as Level 2. Agency Collateralized Mortgage Obligations and Small Business Administration Pooled Securities The valuation model for these securities is volatility-driven and ratings based, and uses multi-dimensional spread tables. The inputs used include benchmark yields, reported trades, new issue data, broker dealer quotes, and collateral performance. If there is at least one significant model assumption or input that is not observable, these securities are categorized as Level 3 within the fair value hierarchy; otherwise, they are classified as Level 2. State, County, and Municipal Securities The fair value is estimated using a valuation matrix with inputs including bond interest rate tables, recent transaction, and yield relationships. These securities are categorized as Level 2. Single and Pooled Issuer Trust Preferred Securities The fair value of trust preferred securities, including pooled and single issuer preferred securities, is estimated using external pricing models, discounted cash flow methodologies or similar techniques. The inputs used in these valuations include benchmark yields, reported trades, new issue data, broker dealer quotes, and collateral performance. If there is at least one significant model assumption or input that is not observable, these securities are classified as Level 3 within the fair value hierarchy; otherwise, they are classified as Level 2. Loans Held for Sale The Company has elected the fair value option to account for originated closed loans intended for sale. The fair value is measured on an individual loan basis using quoted market prices and when not available, comparable market value or discounted cash flow analysis may be utilized. These assets are typically classified as Level 2. Derivative Instruments Derivatives The valuation of these instruments is determined using widely accepted valuation techniques including discounted cash flow analysis on the expected cash flows of each derivative. This analysis reflects the contractual terms of the derivatives, including the period to maturity, and uses observable market-based inputs, including interest rate curves and implied volatilities. The Company incorporates credit valuation adjustments to appropriately reflect nonperformance risk in the fair value measurements. In adjusting the fair value of its derivative contracts for the effect of nonperformance risk, the Company has considered the impact of netting and any applicable credit enhancements, such as collateral postings. Additionally, in conjunction with fair value measurement guidance, the Company has made an accounting policy election to measure the credit risk of its derivative financial instruments that are subject to master netting agreements on a net basis by counterparty portfolio. Although the Company has determined that the majority of the inputs used to value its interest rate derivatives fall within Level 2 of the fair value hierarchy, the credit valuation adjustments associated with its derivatives utilize Level 3 inputs, such as estimates of current credit spreads to evaluate the likelihood of default by the Company and its counterparties. However, as of December 31, 2019 and 2018 , the Company has assessed the significance of the impact of the credit valuation adjustments on the overall valuation of its derivative positions and has determined that the credit valuation adjustments are not significant to the overall valuation of its derivatives. As a result, the Company has determined that its derivative valuations in their entirety are classified in Level 2. Mortgage Derivatives The fair value of mortgage derivatives is determined based on current market prices for similar assets in the secondary market and, therefore, classified as Level 2 within the fair value hierarchy. Impaired Loans Collateral dependent loans that are deemed to be impaired are valued based upon the lower of cost or fair value of the underlying collateral less costs to sell. The inputs used in the appraisals of the collateral are not always observable, and therefore the loans may be classified as Level 3 within the fair value hierarchy; otherwise, they are classified as Level 2. Other Real Estate Owned and Other Foreclosed Assets The fair values are generally estimated based upon recent appraisal values of the property less costs to sell the property, as Other Real Estate Owned ("OREO") and Other Foreclosed Assets are valued at the lower of cost or fair value of the property, less estimated costs to sell. Certain inputs used in appraisals are not always observable, and therefore OREO and Other Foreclosed Assets are classified as Level 3 within the fair value hierarchy. Goodwill and Other Intangible Assets Goodwill and identified intangible assets are subject to impairment testing. The Company conducts an annual impairment test of goodwill in the third quarter of each year, or more frequently if necessary, and other intangible assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets may not be recoverable. To estimate the fair value of goodwill and, if necessary, other intangible assets, the Company utilizes both a comparable analysis of relevant price multiples in recent market transactions and discounted cash flow analysis. Both valuation models require a significant degree of management judgment. In the event the fair value as determined by the valuation model is less than the carrying value, the intangibles may be impaired. If the impairment testing resulted in impairment, the Company would classify the impaired goodwill and other intangible assets subjected to nonrecurring fair value adjustments as Level 3. Assets and liabilities measured at fair value on a recurring and nonrecurring basis were as follows as of the dates indicated: Fair Value Measurements at Reporting Date Using Balance Quoted Prices in Significant Other Significant December 31, 2019 (Dollars in thousands) Recurring fair value measurements Assets Trading securities $ 2,179 $ 2,179 $ — $ — Equity securities 21,261 21,261 — — Securities available for sale U.S. government agency securities 33,115 — 33,115 — Agency mortgage-backed securities 247,000 — 247,000 — Agency collateralized mortgage obligations 88,511 — 88,511 — State, county, and municipal securities 1,396 — 1,396 — Single issuer trust preferred securities issued by banks and insurers 493 — 493 — Pooled trust preferred securities issued by banks and insurers 1,114 — — 1,114 Small business administration pooled securities 54,795 — 54,795 — Loans held for sale 33,307 — 33,307 — Derivative instruments 78,385 — 78,385 — Liabilities Derivative instruments 53,923 — 53,923 — Total recurring fair value measurements $ 507,633 $ 23,440 $ 483,079 $ 1,114 Nonrecurring fair value measurements Assets Collateral dependent impaired loans $ 25,515 $ — $ — $ 25,515 Total nonrecurring fair value measurements $ 25,515 $ — $ — $ 25,515 Fair Value Measurements at Reporting Date Using Balance Quoted Prices in Significant Other Significant December 31, 2018 (Dollars in thousands) Recurring fair value measurements Assets Trading securities $ 1,504 $ 1,504 $ — $ — Equity securities 19,477 19,477 — — Securities available for sale U.S. government agency securities 32,038 — 32,038 — Agency mortgage-backed securities 220,105 — 220,105 — Agency collateralized mortgage obligations 134,911 — 134,911 — State, county, and municipal securities 1,735 — 1,735 — Single issuer trust preferred securities issued by banks and insurers 707 — 707 — Pooled trust preferred securities issued by banks and insurers 1,329 — — 1,329 Small business administration pooled securities 51,927 — 51,927 — Loans held for sale 6,431 — 6,431 — Derivative instruments 26,310 — 26,310 — Liabilities Derivative instruments 17,523 — 17,523 — Total recurring fair value measurements $ 478,951 $ 20,981 $ 456,641 $ 1,329 Nonrecurring fair value measurements: Assets Collateral dependent impaired loans $ 29,109 $ — $ — $ 29,109 Total nonrecurring fair value measurements $ 29,109 $ — $ — $ 29,109 All assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) were valued using pricing models and discounted cash flow methodologies, as of December 31, 2019 , 2018 and 2017 . This reconciliation is presented in the table below for the periods indicated: 2019 2018 2017 (Dollars in thousands) Pooled Trust Preferred Securities Beginning balance $ 1,329 $ 1,640 $ 1,584 Gain and (losses) (realized/unrealized) Included in earnings — — — Included in other comprehensive income (26 ) 191 77 Settlements (189 ) (502 ) (21 ) Ending Balance $ 1,114 $ 1,329 $ 1,640 The following table sets forth certain unobservable inputs regarding the Company's financial instruments that are classified as Level 3 as of December 31st of the years indicated: Valuation Technique Fair Value Unobservable Inputs Range Weighted Average 2019 2018 2019 2018 2019 2018 (Dollars in thousands) Discounted cash flow methodology Pooled trust preferred securities $ 1,114 $ 1,329 Cumulative prepayment 0% - 57% 0% - 59% 2.6% 2.1% Cumulative default 2% - 100% 5% - 100% 13.5% 16.2% Loss given default 85% - 100% 85% - 100% 93.6% 94.8% Cure given default 0% - 75% 0% - 75% 60.9% 60.9% Appraisals of collateral (1) Collateral dependent impaired loans $ 25,515 $ 29,109 (1) Fair value is generally determined through independent appraisals of the underlying collateral, which generally include various Level 3 inputs which are not identifiable. Appraisals may be adjusted by management for qualitative factors such as economic factors and estimated liquidation expenses. The range of these possible adjustments may vary. The significant unobservable inputs used in the fair value measurement of the Company’s pooled trust preferred securities are cumulative prepayment rates, cumulative defaults, loss given defaults and cure given defaults. Significant increases (decreases) in deferrals or defaults, in isolation, would result in a significantly lower (higher) fair value measurement. Alternatively, significant increases (decreases) in cure rates, in isolation, would result in a significantly higher (lower) fair value measurement. The estimated fair values and related carrying amounts for assets and liabilities for which fair value is only disclosed are shown below as of the dates indicated: Fair Value Measurements at Reporting Date Using Carrying Value Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) December 31, 2019 (Dollars in thousands) Financial assets Securities held to maturity (a) U.S. government agency securities $ 12,874 $ 12,997 $ — $ 12,997 $ — U.S. Treasury securities 4,032 4,053 — 4,053 — Agency mortgage-backed securities 397,414 405,802 — 405,802 — Agency collateralized mortgage obligations 293,662 297,314 — 297,314 — Single issuer trust preferred securities issued by banks 1,500 1,490 — 1,490 — Small business administration pooled securities 31,324 31,607 — 31,607 — Loans, net of allowance for loan losses (b) 8,780,384 8,613,635 — — 8,613,635 Federal Home Loan Bank stock (c) 14,424 14,424 — 14,424 — Cash surrender value of life insurance policies (d) 197,372 197,372 — 197,372 — Financial liabilities Deposit liabilities, other than time deposits (e) $ 7,752,052 $ 7,752,052 $ — $ 7,752,052 $ — Time certificates of deposits (f) 1,395,315 1,396,760 — 1,396,760 — Federal Home Loan Bank borrowings (f) 115,748 115,881 — 115,881 — Long-term borrowings (f) 74,906 72,219 — 72,219 — Junior subordinated debentures (g) 62,848 65,603 — 65,603 — Subordinated debentures (f) 49,601 52,870 — — 52,870 Fair Value Measurements at Reporting Date Using Carrying Value Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) December 31, 2018 Financial assets (Dollars in thousands) Securities held to maturity (a) U.S. Treasury securities $ 1,004 $ 1,015 $ — $ 1,015 $ — Agency mortgage-backed securities 252,484 250,928 — 250,928 — Agency collateralized mortgage obligations 332,775 326,724 — 326,724 — Single issuer trust preferred securities issued by banks 1,500 1,490 — 1,490 — Small business administration pooled securities 23,727 23,483 — 23,483 — Loans, net of allowance for loan losses (b) 6,812,792 6,635,209 — — 6,635,209 Federal Home Loan Bank stock (c) 15,683 15,683 — 15,683 — Cash surrender value of life insurance policies (d) 160,456 160,456 — 160,456 — Financial liabilities Deposit liabilities, other than time deposits (e) $ 6,716,017 $ 6,716,017 $ — $ 6,716,017 $ — Time certificates of deposits (f) 711,103 703,728 — 703,728 — Federal Home Loan Bank borrowings (f) 147,806 147,603 — 147,603 — Junior subordinated debentures (g) 76,173 73,827 — 73,827 — Subordinated debentures (f) 34,728 32,509 — — 32,509 (a) The fair values presented are based on quoted market prices, where available. If quoted market prices are not available, fair values are based on quoted market prices of comparable instruments and/or discounted cash flow analysis. (b) Fair value of loans is measured using the exit price valuation method, determined primarily by discounting the future cash flows using the current rates at which similar loans would be made to borrowers with similar credit ratings and for the same remaining maturities or cash flows, while incorporating liquidity and credit assumptions. Additionally, this amount excludes collateral dependent impaired loans, which are deemed to be marked to fair value on a nonrecurring basis. (c) FHLB stock has no quoted market value and is carried at cost, therefore the carrying amount approximates fair value. (d) Cash surrender value of life insurance is recorded at its cash surrender value (or the amount that can be realized upon surrender of the policy), therefore carrying amount approximates fair value. (e) Fair value of demand deposits, savings and interest checking accounts and money market deposits is the amount payable on demand at the reporting date. (f) Fair value was determined by discounting anticipated future cash payments using rates currently available for instruments with similar remaining maturities. (g) Fair value was determined based upon market prices of securities with similar terms and maturities. This summary excludes certain financial assets and liabilities for which the carrying value approximates fair value. For financial assets, these may include cash and due from banks, federal funds sold and short-term investments. For financial liabilities, these may include federal funds purchased. These instruments would all be considered to be classified as Level 1 within the fair value hierarchy. Also excluded from the summary are financial instruments measured at fair value on a recurring and nonrecurring basis, as previously described. The Company considers its financial instruments' current use to be the highest and best use of the instruments.

REVENUE RECOGNITION (Notes)

REVENUE RECOGNITION (Notes)	12 Months Ended
	Dec. 31, 2019
Revenue Recognition [Abstract]
Revenue from Contract with Customer [Text Block]	REVENUE RECOGNITION A portion of the Company's noninterest income is derived from contracts with customers, and as such, the revenue recognized depicts the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The Company considers the terms of the contract and all relevant facts and circumstances when applying this guidance. To ensure its alignment with this core principle, the Company measures revenue and the timing of recognition by applying the following five steps: 1. Identify the contract(s) with customers 2. Identify the performance obligations 3. Determine the transaction price 4. Allocate the transaction price to the performance obligations 5. Recognize revenue when (or as) the entity satisfies a performance obligation The Company has disaggregated its revenue from contracts with customers into categories that depict how the nature, amount, timing, and uncertainty of revenue and cash flows are affected by economic factors. The following table presents the revenue streams that the Company has disaggregated for the periods indicated: Years Ended December 31 2019 2018 2017 (Dollars in thousands) Deposit account fees (inclusive of cash management fees) $ 20,040 $ 18,327 $ 17,822 Interchange fees 18,262 15,433 13,899 ATM fees 3,224 2,961 2,938 Investment management - wealth management and advisory services 25,940 23,441 21,644 Investment management - retail investments and insurance revenue 2,779 2,714 2,158 Merchant processing income 1,175 1,401 1,229 Other noninterest income 8,696 4,432 4,569 Total noninterest income in-scope of ASC 606 80,116 68,709 64,259 Total noninterest income out-of-scope of ASC 606 35,178 19,796 18,735 Total noninterest income $ 115,294 88,505 $ 82,994 In each of the revenue streams identified above, there were no significant judgments made in determining or allocating the transaction price, as the consideration and service requirements are generally explicitly identified in the associated contracts. Additional information related to each of the revenue streams is further noted below: Deposit Account Fees The Company offers various deposit account products to its customers governed by specific deposit agreements applicable to either personal customers or business customers. These agreements identify the general conditions and obligations of both parties, and include standard information regarding deposit account related fees. Deposit account services include providing access to deposit accounts as well as access to the various deposit transactional services of the Company. These transactional services are primarily those that are identified in the standard fee schedule, and include, but are not limited to, services such as overdraft protection, wire transfer, and check collection. Revenue is recognized in conjunction with the various services being provided. For example, the Company may assess monthly fixed service fees associated with the customer having access to the deposit account, which can vary depending on the account type and daily account balance. In addition, the Company may also assess separate fixed fees associated with and at the time specific transactions are entered in to by the customer. As such, the Company considers its performance obligations to be met concurrently with providing the account access or completing the requested deposit transaction. Cash Management Cash management services are a subset of the Deposit account fees revenue stream. These services primarily include ACH transaction processing, positive pay and remote deposit services. These services are also governed by separate agreements entered into with the customer. The fee arrangement for these services is structured to assess fees under one of two scenarios, either a per transaction fee arrangement or an earnings credit analysis arrangement. Under the per transaction fee arrangement, fixed fees are assessed concurrently with customers executing the transactions, and as such, the Company considers its performance obligations to be met concurrently with completing the requested transaction. Under the earnings credit analysis arrangement, the Company provides a monthly earnings credit to the customer that is negotiated and determined based on various factors. The credit is then available to absorb the per transaction fees that are assessed on the customer's deposit account activity for the month. Any amount of the transactional fees in excess of the earnings credit is recognized as revenue in that month. Interchange Fees The Company earns interchange revenue from its issuance of credit and debit cards granted through its membership in various card payment networks. The Company provides credit cards and debit cards to its customers which are authorized and settled through these payment networks, and in exchange, the Company earns revenue as determined by each payment network's interchange program. The revenue is recognized concurrently with the settlement of card transactions within each network. ATM Fees The Company deploys automated teller machines (ATMs) as part of its overall branch network. Certain transactions performed at the ATMs require customers to acknowledge and pay a fee for the requested service. Certain ATM fees are disclosed in the deposit account agreement fee schedules, whereas those assessed to non-Rockland Trust deposit holders are solely determined during the transaction at the machine. The ATM fee is a fixed dollar per transaction amount, and as such, is recognized concurrently with the overall daily processing and settlement of the ATM activity. Investment Management - Wealth Management and Advisory Services The Company offers investment management and trust services to individuals, institutions, small businesses and charitable institutions. Each investment management product is governed by its own contract along with a separate identifiable fee schedule unique to that product. The Company also offers additional services, such as estate settlement, financial planning, tax services and other special services quoted at the client's request. The asset management and/or custody fees are based upon a percentage of the monthly valuation of the principal assets in the customer's account, whereas fees for additional or special services are fixed in nature and are charged as services are rendered. As the fees are dependent on assets under management, which are susceptible to market factors outside of the Company's control, this variable consideration is constrained and therefore no revenue is estimated at contract initiation. As such, all revenue is recognized in correlation to the monthly management fee determinations or as transactional services are provided. Due to the fact that payments are primarily made subsequent to the valuation period, the Company records a receivable for revenue earned but not received. The following table provides the amount of investment management revenue earned but not received as of the dates indicated: December 31, 2019 December 31, 2018 (Dollars in thousands) Receivables, included in other assets $ 2,341 $ 1,893 Investment Management - Retail Investments and Insurance Revenue The Company offers the sale of mutual fund shares, unit investment trust shares, general securities, fixed and variable annuities and life insurance products through registered representatives who are both employed by the Company and licensed and contracted with various Broker General Agents to offer these products to the Company’s customer base. As such, the Company performs these services as an agent and earns a fixed commission on the sales of these products and services. To a lesser degree, production bonus commissions can also be earned based upon the Company meeting certain volume thresholds. In general, the Company recognizes commission revenue at the point of sale, and for certain insurance products, may also earn and recognize annual residual commissions commensurate with annual premiums being paid. Merchant Processing Income The Company refers customers to third party merchant processing partners in exchange for commission and fee income. The income earned is comprised of multiple components, including a fixed referral fee per each referred customer, a rebate amount determined primarily as a percentage of net revenue earned by the third party from services provided to each referred customer, and overall production bonus commissions if certain new account production thresholds are met. Merchant processing income is recognized in conjunction with either completing the referral to earn the fixed fee amount or as the merchant activity is processed to derive the Company's rebate and/or production bonus amounts. Other Noninterest Income The Company earns various types of other noninterest income that fall within the scope of the new revenue recognition rules, and have been aggregated into one general revenue stream in the table noted above. This amount includes, but is not limited to, the following types of revenue with customers: Safe Deposit Rent The Company rents out the use of safe deposit boxes to its customers, which can be accessed when the bank is open for business. The safe deposit box rental fee is paid upfront and is recognized as revenue ratably over the annual term of the contract. 1031 Exchange Fee Revenue The Company provides like-kind exchange services pursuant to Section 1031 of the Internal Revenue Code. Fee income is recognized in conjunction with completing the exchange transactions. Foreign Currency

OTHER COMPREHENSIVE LOSS

OTHER COMPREHENSIVE LOSS	12 Months Ended
	Dec. 31, 2019
Equity [Abstract]
OTHER COMPREHENSIVE LOSS	OTHER COMPREHENSIVE INCOME (LOSS) The following table presents a reconciliation of the changes in the components of other comprehensive income (loss) for the periods indicated, including the amount of income tax (expense) benefit allocated to each component of other comprehensive income (loss): Year Ended December 31, 2019 Pre Tax Tax (Expense) After Tax (Dollars in thousands) Change in fair value of securities available for sale $ 12,055 $ (2,761 ) $ 9,294 Less: net security losses reclassified into other noninterest expense (1,462 ) 411 (1,051 ) Net change in fair value of securities available for sale 13,517 (3,172 ) 10,345 Change in fair value of cash flow hedges 16,725 (4,708 ) 12,017 Less: net cash flow hedge gains reclassified into interest income or interest expense 2,346 (660 ) 1,686 Net change in fair value of cash flow hedges 14,379 (4,048 ) 10,331 Net unamortized loss related to defined benefit pension and other postretirement adjustments arising during the period (2,123 ) 597 (1,526 ) Amortization of net actuarial gains (8 ) 2 (6 ) Amortization of net prior service costs 276 (78 ) 198 Net change in other comprehensive income for defined benefit postretirement plans (2) (1,855 ) 521 (1,334 ) Total other comprehensive income $ 26,041 $ (6,699 ) $ 19,342 Year Ended December 31, 2018 Pre Tax Tax (Expense) After Tax (Dollars in thousands) Change in fair value of securities available for sale $ (5,923 ) $ 1,422 $ (4,501 ) Less: net security gains reclassified into other noninterest income (expense) — — — Net change in fair value of securities available for sale (5,923 ) 1,422 (4,501 ) Change in fair value of cash flow hedges 7,717 (2,169 ) 5,548 Less: net cash flow hedge losses reclassified into interest income or interest expense (1) 1,000 (281 ) 719 Net change in fair value of cash flow hedges 6,717 (1,888 ) 4,829 Net unamortized gain related to defined benefit pension and other postretirement adjustments arising during the period 1,521 (428 ) 1,093 Amortization of net actuarial losses 372 (105 ) 267 Amortization of net prior service costs 276 (78 ) 198 Net change in other comprehensive income for defined benefit postretirement plans (2) 2,169 (611 ) 1,558 Total other comprehensive income $ 2,963 $ (1,077 ) $ 1,886 Year Ended December 31, 2017 Pre Tax Tax (Expense) After Tax (Dollars in thousands) Change in fair value of securities available for sale $ (996 ) $ 321 $ (675 ) Less: net security gains reclassified into other noninterest income (expense) 3 (1 ) 2 Net change in fair value of securities available for sale (999 ) 322 (677 ) Change in fair value of cash flow hedges 307 (125 ) 182 Less: net cash flow hedge losses reclassified into interest income or interest expense (1) (441 ) 180 (261 ) Net change in fair value of cash flow hedges 748 (305 ) 443 Net unamortized loss related to defined benefit pension and other postretirement adjustments arising during the period (995 ) 407 (588 ) Amortization of net actuarial losses 278 (113 ) 165 Amortization of net prior service costs 276 (113 ) 163 Net change in other comprehensive income for defined benefit postretirement plans (2) (441 ) 181 (260 ) Total other comprehensive loss $ (692 ) $ 198 $ (494 ) (1) Includes the amortization of the remaining balance of a realized but unrecognized gain, net of tax, from the termination of interest rate swaps in 2009. The original gain of $1.4 million , net of tax, was recognized in earnings through December 2018 , the original maturity date of the swap. The balance of the gain was amortized to $137,000 at December 31, 2017 . (2) The amortization of prior service costs is included in the computation of net periodic pension costs as disclosed in Note 15 - Employee Benefit Plans . Effective January 1, 2018, the Company elected to reclassify certain tax effects from accumulated other comprehensive income to retained earnings, related to items that were stranded in other comprehensive income as a result of the Tax Act. A description of the other income tax effects that were reclassified as a result of the Tax Act are listed in the table below. Information on the Company's accumulated other comprehensive income (loss), net of tax, is comprised of the following components for the periods indicated: Unrealized Gain (Loss) on Securities Unrealized Gain (Loss) on Cash Flow Hedge Deferred Gain on Hedge Transactions Defined Benefit Postretirement Plans Accumulated Other Comprehensive Income (Loss) (Dollars in Thousands) Beginning balance: January 1, 2017 $ 173 $ 361 $ 281 $ (2,152 ) $ (1,337 ) Other comprehensive income (loss) (677 ) 587 (144 ) (260 ) (494 ) Ending balance: December 31, 2017 $ (504 ) $ 948 $ 137 $ (2,412 ) $ (1,831 ) Opening balance reclassification (111 ) 205 29 (520 ) (397 ) Cumulative effect accounting adjustment (831 ) — — — (831 ) Other comprehensive income (loss) (4,501 ) 4,995 (166 ) 1,558 1,886 Ending balance: December 31, 2018 $ (5,947 ) $ 6,148 $ — $ (1,374 ) $ (1,173 ) Other comprehensive income (loss) 10,345 10,331 — (1,334 ) 19,342 Ending balance: December 31, 2019 $ 4,398 $ 16,479 $ — $ (2,708 ) $ 18,169

LEASES (Notes)

LEASES (Notes)	12 Months Ended
	Dec. 31, 2019
Leases [Abstract]
Lessee, Operating Leases [Text Block]	LEASES The Company adopted the new lease accounting standard ("the lease standard") under Accounting Standards Codification Topic 842 ("ASC 842") using the modified retrospective transition method with an effective date as of January 1, 2019. Therefore, periods prior to that date were not restated, and accordingly disclosures are not presented on a comparable basis. The Company elected the package of practical expedients, which permits the Company not to reassess prior conclusions about lease identifications, lease classification and initial direct costs. The Company did not elect to apply the hindsight practical expedient pertaining to using hindsight knowledge as of the effective date when determining lease terms and impairment. As of December 31, 2019 , the Company has entered into 94 noncancelable operating lease agreements for office space, space for ATM locations and certain branch locations, several of which contain renewal options to extend lease terms for a period of 1 to 10 years. The Company has no financing leases outstanding and no leases with residual value guarantees. As of December 31, 2019 , the Company does not have any material sub-lease agreements. The Company's right-of-use asset related to operating leases was $56.6 million at December 31, 2019 and is recognized in the Company's Consolidated Balance Sheet in other assets. The following table provides information related to the Company's lease cost: For the year ended December 31, 2019 (Dollars in thousands) Operating lease cost $10,718 Short-term lease cost 116 Variable lease cost — Total lease cost $10,834 As of December 31, 2019 , the weighted average remaining lease term for operating leases was 6.43 years and the weighted average discount rate used in the measurement of operating lease liabilities was 2.75% . The following table sets forth the undiscounted cash flows of base rent related to operating leases outstanding at December 31, 2019 with payments scheduled over the next five years and thereafter, including a reconciliation to the operating lease liability recognized in the Company's Consolidated Balance Sheet in other liabilities: (Dollars in thousands) 2020 $ 11,752 2021 11,052 2022 10,438 2023 8,528 2024 7,121 Thereafter 14,900 Total minimum lease payments 63,791 Less: amount representing interest 5,489 Present value of future minimum lease payments $ 58,302

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Financial Instruments with Off-Balance Sheet Risk In the normal course of business, the Company enters into various transactions to meet the financing needs of its customers, which, in accordance with GAAP, are not included in its consolidated balance sheets. These transactions include commitments to extend credit, standby letters of credit, and loans sold with recourse, which involve, to varying degrees, elements of credit risk and interest rate risk in excess of the amounts recognized in the consolidated balance sheets. The Company minimizes its exposure to loss under these commitments by subjecting them to credit approval and monitoring procedures. The Company enters into contractual commitments to extend credit, normally with fixed expiration dates or termination clauses, at specified rates and for specific purposes. Substantially all of these commitments to extend credit are contingent upon customers maintaining specific credit standards at the time of loan funding. Standby letters of credit are written conditional commitments issued to guarantee the performance of a customer to a third party. In the event the customer does not perform in accordance with the terms of the agreement with the third party, the Company would be required to fund the commitment. The maximum potential amount of future payments the Company could be required to make is represented by the contractual amount of the commitment. If the commitment were funded, the Company would be entitled to seek recovery from the customer. The Company’s policies generally require that standby letter of credit arrangements contain security and debt covenants similar to those contained in loan agreements. The fees collected in connection with the issuance of standby letters of credit are representative of the fair value of the obligation undertaken in issuing the guarantee. In accordance with applicable accounting standards related to guarantees, fees collected in connection with the issuance of standby letters of credit are deferred. The fees are then recognized in income proportionately over the life of the standby letter of credit agreement. The deferred standby letter of credit fees represent the fair value of the Company's potential obligations under the standby letter of credit guarantees. The following table summarizes the above financial instruments at the dates indicated: As of December 31 2019 2018 (Dollars in thousands) Commitments to extend credit $ 3,337,930 $ 2,639,689 Standby letters of credit $ 21,565 $ 16,708 Deferred standby letter of credit fees $ 158 $ 122 Loans sold with recourse $ 404,532 $ — Other Contingencies At December 31, 2019 , Rockland Trust was involved in pending lawsuits that arose in the ordinary course of business. Management has reviewed these pending lawsuits with legal counsel and has taken into consideration the view of counsel as to their outcome. In the opinion of management, the final disposition of pending lawsuits is not expected to have a material adverse effect on the Company’s financial position or results of operations. The Bank is required to maintain certain reserve requirements of vault cash and/or deposits with the Federal Reserve Bank of Boston. There was no reserve requirement balance necessary at December 31, 2019 . The amount of the reserve was $53.5 million at December 31, 2018 .

REGULATORY CAPITAL REQUIREMENTS

REGULATORY CAPITAL REQUIREMENTS	12 Months Ended
	Dec. 31, 2019
Banking and Thrift [Abstract]
REGULATORY CAPITAL REQUIREMENTS	REGULATORY MATTERS Regulatory Capital Requirements The Company and the Bank are subject to various regulatory capital requirements administered by the federal banking agencies. Failure to meet minimum capital requirements can initiate certain mandatory and possibly additional discretionary actions by regulators that, if undertaken, could have a direct material effect on the Company’s financial statements. Under capital adequacy guidelines and the regulatory framework for prompt corrective action, the Company and the Bank must meet specific capital guidelines that involve quantitative measures of the Company’s and the Bank’s assets, liabilities and certain off-balance sheet items as calculated under regulatory accounting practices. The capital amounts and classification are also subject to qualitative judgments by the regulators about components, risk weightings and other factors. At December 31, 2019 the most recent notification from the Federal Deposit Insurance Corporation indicated that the Bank's capital levels met or exceeded the minimum levels to be considered "well capitalized" for bank regulatory purposes. To be categorized as well capitalized, an institution must maintain minimum total risk-based, Tier 1 risk-based, Common equity Tier 1 risk-based and Tier 1 leverage ratios as set forth in the following tables. There are no conditions or events since the notification that management believes have changed the Bank’s category. Management believes, as of December 31, 2019 and 2018 , that the Company and the Bank met all capital adequacy requirements to which they are subject. The Company’s and the Bank’s actual capital amounts and ratios as of December 31, 2019 and 2018 are also presented in the table that follows: Actual For Capital To Be Well Capitalized Amount Ratio Amount Ratio Amount Ratio December 31, 2019 (Dollars in thousands) Independent Bank Corp. Total capital (to risk weighted assets) $ 1,352,341 14.83 % $ 729,291 ≥ 8.0 % N/A N/A Common equity tier 1 capital (to risk weighted assets) $ 1,171,963 12.86 % $ 410,226 ≥ 4.5 % N/A N/A Tier 1 capital (to risk weighted assets) $ 1,232,963 13.53 % $ 546,969 ≥ 6.0 % N/A N/A Tier 1 capital (to average assets) leverage $ 1,232,963 11.28 % $ 437,271 ≥ 4.0 % N/A N/A Rockland Trust Company Total capital (to risk weighted assets) $ 1,275,611 14.00 % $ 728,868 ≥ 8.0 % $ 911,085 ≥ 10.0 % Common equity tier 1 capital (to risk weighted assets) $ 1,205,740 13.23 % $ 409,988 ≥ 4.5 % $ 592,205 ≥ 6.5 % Tier 1 capital (to risk weighted assets) $ 1,205,740 13.23 % $ 546,651 ≥ 6.0 % $ 728,868 ≥ 8.0 % Tier 1 capital (to average assets) leverage $ 1,205,740 11.06 % $ 435,886 ≥ 4.0 % $ 544,857 ≥ 5.0 % December 31, 2018 (Dollars in thousands) Independent Bank Corp. Total capital (to risk weighted assets) $ 992,454 14.45 % $ 549,297 ≥ 8.0 % N/A N/A Common equity tier 1 capital (to risk weighted assets) $ 818,176 11.92 % $ 308,980 ≥ 4.5 % N/A N/A Tier 1 capital (to risk weighted assets) $ 892,176 12.99 % $ 411,973 ≥ 6.0 % N/A N/A Tier 1 capital (to average assets) $ 892,176 10.69 % $ 333,754 ≥ 4.0 % N/A N/A Rockland Trust Company Total capital (to risk weighted assets) $ 937,574 13.66 % $ 549,036 ≥ 8.0 % $ 686,295 ≥ 10.0 % Common equity tier 1 capital (to risk weighted assets) $ 872,024 12.71 % $ 308,833 ≥ 4.5 % $ 446,092 ≥ 6.5 % Tier 1 capital (to risk weighted assets) $ 872,024 12.71 % $ 411,777 ≥ 6.0 % $ 549,036 ≥ 8.0 % Tier 1 capital (to average assets) $ 872,024 10.46 % $ 333,595 ≥ 4.0 % $ 416,994 ≥ 5.0 % In addition to the minimum risk-based capital requirements outlined in the table above, the Company is required to maintain a minimum capital conservation buffer, in the form of common equity, in order to avoid restrictions on capital distributions and discretionary bonuses. The required amount of the capital conservation buffer is 2.5%. The Company's capital levels exceeded the minimum requirement plus the buffer of 2.5% as of December 31, 2019 and 2018 . Dividend Restrictions In the ordinary course of business, the Company is dependent upon dividends from the Bank to provide funds for the payment of dividends to shareholders and to provide for other cash requirements. Banking regulations may limit the amount of dividends that may be paid. Approval by regulatory authorities is required if the effect of dividends declared would cause the regulatory capital of the Bank to fall below specified minimum levels. Approval is also required if dividends declared exceed the net profits for that year combined with the retained net profits for the preceding two years. Under the foregoing dividend restrictions and while maintaining its "well capitalized" status, dividends paid by the Bank to the Company for the year ended December 31, 2019 and 2018 totaled $181.7 million and $71.2 million , respectively. Trust Preferred Securities In accordance with the applicable accounting standard related to variable interest entities, the common stock of trusts which have issued trust preferred securities have not been included in the consolidated financial statements. At December 31, 2019 and 2018 , there was $61.0 million and $74.0 million , respectively, in trust preferred securities that have been included in the Tier 1 capital of the Company for regulatory reporting purposes pursuant to the Federal Reserve's capital adequacy guidelines. The decrease in 2019 was due to the redemption of trust preferred securities of $13.0 million

PARENT COMPANY FINANCIALS ONLY

PARENT COMPANY FINANCIALS ONLY	12 Months Ended
	Dec. 31, 2019
Condensed Financial Information Disclosure [Abstract]
PARENT COMPANY FINANCIAL STATEMENTS	PARENT COMPANY FINANCIAL STATEMENTS Condensed financial information relative to the Parent Company’s balance sheets at December 31, 2019 and 2018 and the related statements of income and cash flows for the years ended December 31, 2019 , 2018 , and 2017 are presented below. The statement of stockholders’ equity is not presented below as the parent company’s stockholders’ equity is that of the consolidated Company. BALANCE SHEETS December 31 2019 2018 (Dollars in thousands) Assets Cash (1) $ 135,688 $ 64,256 Investments in subsidiaries (2) 1,743,435 1,128,407 Prepaid income taxes 31,586 1,014 Deferred tax asset 612 — Derivative instruments (1) 290 1,711 Other assets — 37 Total assets $ 1,911,611 $ 1,195,425 Liabilities and stockholders’ equity Dividends payable $ 15,126 $ 10,671 Long-term borrowings (less unamortized debt issuance costs of $94) 74,906 — Junior subordinated debentures (less unamortized debt issuance costs of $40 and $118) 62,848 76,173 Subordinated debentures (less unamortized debt issuance costs of $399 and $272) 49,601 34,728 Other liabilities 987 363 Total liabilities 203,468 121,935 Stockholders’ equity 1,708,143 1,073,490 Total liabilities and stockholders’ equity $ 1,911,611 $ 1,195,425 (1) Entire balance eliminates in consolidation. (2) Majority of balance eliminates in consolidation. STATEMENTS OF INCOME Years Ended December 31 2019 2018 2017 (Dollars in thousands) Income Dividends received from subsidiaries (1) $ 181,790 $ 71,255 $ 47,006 Interest income (2) — — 50 Total income 181,790 71,255 47,056 Expenses Interest expense 8,236 4,234 3,995 Total expenses 8,236 4,234 3,995 Income before income taxes and equity in undistributed income of subsidiaries 173,554 67,021 43,061 Income tax benefit (2,262 ) (1,151 ) (1,523 ) Income of parent company 175,816 68,172 44,584 Equity (deficit) in undistributed income of subsidiaries (10,641 ) 53,450 42,620 Net income $ 165,175 $ 121,622 $ 87,204 (1) Majority of balance eliminates in consolidation. (2) Entire balance eliminated in consolidation. STATEMENTS OF CASH FLOWS Years Ended December 31 2019 2018 2017 (Dollars in thousands) Cash flows from operating activities Net income $ 165,175 $ 121,622 $ 87,204 Adjustments to reconcile net income to cash provided by operating activities Amortization 157 54 12 Deferred income tax expense 1,021 49 51 Change in prepaid income taxes and other assets 20,556 135 (99 ) Change in other liabilities (4,613 ) 6 (562 ) Deficit (equity) in undistributed income of subsidiaries 10,641 (53,450 ) (42,620 ) Net cash provided by operating activities 192,937 68,416 43,986 Cash flows provided by (used in) investing activities Cash paid for acquisitions, net of cash acquired (1) (148,297 ) (13,649 ) (4,834 ) Net cash used in investing activities (148,297 ) (13,649 ) (4,834 ) Cash flows used in financing activities Proceeds from line of credit, net of issuance costs 49,980 — — Repayment of line of credit, net of issuance costs (49,980 ) — — Proceeds from long-term debt, net of issuance costs 74,867 — — Repayments of junior subordinated debentures, net of issuance costs (13,329 ) — — Proceeds from issuance of subordinated debentures, net of issuance costs 49,526 — — Repayments of subordinated debentures, net of issuance costs (34,767 ) — — Restricted stock awards issued, net of awards surrendered (1,463 ) (1,371 ) (1,422 ) Net proceeds from exercise of stock options 281 184 214 Proceeds from shares issued under the direct stock purchase plan 4,951 2,712 1,636 Common dividends paid (53,274 ) (40,167 ) (34,045 ) Net cash provided by (used in) financing activities 26,792 (38,642 ) (33,617 ) Net increase in cash and cash equivalents 71,432 16,125 5,535 Cash and cash equivalents at the beginning of the year 64,256 48,131 42,596 Cash and cash equivalents at the end of the year $ 135,688 $ 64,256 $ 48,131 (1) The majority of the net assets acquired at the parent company represented each of the acquired companies' investments in their wholly owned subsidiaries, which were eliminated in consolidation at December 31, 2019 , 2018 , and 2017 , respectively.

SELECTED QUARTERLY FINANCIAL DA

SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED)	12 Months Ended
	Dec. 31, 2019
Quarterly Financial Information Disclosure [Abstract]
SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED)	SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) First Quarter Second Quarter Third Quarter Fourth Quarter 2019 2018 2019 2018 2019 2018 2019 2018 (Dollars in thousands, except per share data) Interest income $ 91,543 $ 73,749 $ 122,144 $ 79,167 $ 119,624 $ 82,875 $ 113,703 $ 87,910 Interest expense 9,018 5,278 16,125 5,999 15,026 6,641 13,710 7,618 Net interest income 82,525 68,471 106,019 73,168 104,598 76,234 99,993 80,292 Provision for loan losses 1,000 500 1,000 2,000 — 1,075 4,000 1,200 Total noninterest income 21,533 19,863 28,648 21,887 31,816 23,264 33,297 23,491 Total noninterest expenses 56,311 53,451 93,032 52,688 67,533 55,439 67,445 64,391 Provision for income taxes 11,522 6,828 10,007 9,249 17,036 9,969 14,368 8,258 Net income $ 35,225 $ 27,555 $ 30,628 $ 31,118 $ 51,845 $ 33,015 $ 47,477 $ 29,934 Basic earnings per share $ 1.25 $ 1.00 $ 0.89 $ 1.13 $ 1.51 $ 1.20 $ 1.38 $ 1.08 Diluted earnings per share $ 1.25 $ 1.00 $ 0.89 $ 1.13 $ 1.51 $ 1.20 $ 1.38 $ 1.07 Weighted average common shares (basic) 28,106,184 27,486,573 34,313,492 27,526,653 34,361,176 27,537,841 34,374,953 27,815,437 Common stock equivalents 54,466 67,381 41,878 54,525 39,390 63,499 46,245 58,576 Weighted average common shares (diluted) 28,160,650 27,553,954 34,355,370 27,581,178 34,400,566 27,601,340 34,421,198 27,874,013 Unusual or infrequently occurring items Items within noninterest income Gain on sale of loans $ — $ — $ — $ — $ 951 $ — $ — $ — Total $ — $ — $ — $ — $ 951 $ — $ — $ — Items within noninterest expense Merger and acquisition expense $ 1,032 $ — $ 24,696 $ 434 $ 705 $ 2,688 $ — $ 8,046 Adjustment for tax effect of previously incurred merger and acquisition expense 650 — — — — — — — Items within provision for income taxes Total $ 1,682 $ — $ 24,696 $ 434 $ 705 $ 2,688 $ — $ 8,046

TRANSACTIONS WITH RELATED PARTI

TRANSACTIONS WITH RELATED PARTIES (Notes)	12 Months Ended
	Dec. 31, 2019
Related Party Transactions [Abstract]
Related Party Transactions Disclosure [Text Block]	TRANSACTIONS WITH RELATED PARTIES Certain directors and officers (including their affiliates, certain family members and entities in which they are principal owners) of the Company are customers of and have had, and are expected to have, transactions with the Company, within the ordinary course of business. These transactions include, but are not limited to, lending activities, deposit services, investment management, and property lease commitments. In the opinion of management, such transactions are consistent with prudent banking practices and are within applicable banking regulations. Further details relating to certain related party transactions are outlined below: Lending Activities The following information represents annual activity of loans to related parties for the periods indicated: 2019 2018 (Dollars in thousands) Principal balance of loans outstanding at beginning of year $ 41,170 $ 52,458 Loan advances (1) 49,771 14,862 Loan payments/payoffs (35,111 ) (14,057 ) Reduction for retired directors — (12,093 ) Principal balance of loans outstanding at end of year $ 55,830 $ 41,170 (1) The 2019 amount includes $7.0 million of BHB acquired loans associated with a director during the year, which represent the outstanding loan balances at the effective date of appointment. At December 31, 2019 and 2018 , there were no loans to related parties which were past due, on nonaccrual status or that had been restructured as part of a troubled debt restructuring. Deposits At December 31, 2019 and 2018 , the amount of deposit balances of related parties totaled $13.0 million and $10.8 million , respectively. Lease Commitments There were no material leases with related parties during the years ended December 31, 2019 and 2018

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
PRINCIPLES OF CONSOLIDATION	The consolidated financial statements include the accounts of the Company, the Bank and other wholly-owned subsidiaries, except subsidiaries that are not deemed necessary to be consolidated. All significant intercompany balances and transactions have been eliminated in consolidation. The Company determines whether it has a controlling financial interest in an entity by first evaluating whether the entity is a voting interest entity or a variable interest entity under GAAP. Voting interest entities are entities in which the total equity investment at risk is sufficient to enable the entity to finance itself independently and provides the equity holders with the obligation to absorb losses, the right to receive residual returns and the right to make decisions about the entity’s activities. The Company would consolidate voting interest entities in which it has all, or at least a majority of, the voting interest. As defined in applicable accounting standards, variable interest entities ("VIEs") are entities that lack one or more of the characteristics of a voting interest entity. A controlling financial interest in a VIE is present when the Company has both the power and ability to direct the activities of the VIE that most significantly impact the VIE's economic performance and an obligation to absorb losses or the right to receive benefits that could potentially be significant to the VIE. The Company also owns the common stock of various trusts which have issued trust preferred securities. These trusts are VIEs in which the Company is not the primary beneficiary and, therefore, are not consolidated. The trust's only assets are junior subordinated debentures issued by the Company, which were acquired by the trust using the proceeds from the issuance of the trust preferred securities and common stock. The junior subordinated debentures are included in long-term debt and the Company’s equity interest in the trust is included in other assets in the accompanying Consolidated Balance Sheets. Interest expense on the junior subordinated debentures is reported in interest expense on long-term debt in the accompanying Consolidated Statements of Income.
RECLASSIFICATION	Reclassification Certain previously reported amounts have been reclassified to conform to the current year’s presentation.
USE OF ESTIMATES	Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America ("GAAP") requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting periods. Actual results could vary from these estimates. Material estimates that are particularly susceptible to significant changes in the near-term relate to the determination of the allowance for loan losses, income taxes, valuation and potential impairment of investment securities, other-than-temporary impairment ("OTTI") of certain investment securities, as well as valuation of goodwill and other intangibles and their respective analyses of impairment.
SIGNIFICANT CONCENTRATIONS OF CREDIT RISK	Significant Concentrations of Credit Risk The vast majority of the Bank’s lending activities are conducted in Massachusetts and Rhode Island. The Bank originates commercial and industrial loans, commercial and residential real estate loans, including construction loans, small business loans, home equity loans, and other consumer loans for its portfolio. The Bank considers a concentration of credit to a particular industry to exist when the aggregate credit exposure which includes direct, indirect or contingent obligations to a borrower, an affiliated group of borrowers or a nonaffiliated group of borrowers engaged in one industry, exceeds 10% of the Bank’s loan portfolio. Loans originated by the Bank to lessors of nonresidential buildings represented 17.5% and 15.1% of the total loan portfolio at December 31, 2019 and 2018 , respectively. Within this concentration category, the Company believes it is well diversified among collateral property types and tenant industries.
CASH AND CASH EQUIVALENTS	Cash and Cash Equivalents For purposes of reporting cash flows, cash and cash equivalents may include cash on hand, amounts due from banks, inclusive of interest-earning deposits held at banks, and federal funds sold. Generally, federal funds are sold for up to two week periods.
SECURITIES	Investment securities are classified at the time of purchase as available for sale, held to maturity, trading, or equity. Classification is constantly re-evaluated for consistency with corporate goals and objectives. Trading and equity securities are recorded at fair value with subsequent changes in fair value recorded in earnings. Debt securities that management has the positive intent and ability to hold to maturity are classified as held to maturity and recorded at amortized cost. Debt securities not classified as held to maturity or trading are classified as available for sale and recorded at fair value, with changes in fair value excluded from earnings and reported in other comprehensive income, net of related tax. Purchase premiums and discounts are recognized in interest income, using the interest method, to arrive at periodic interest income at a constant effective yield, thereby reflecting the securities market yield. Gains and losses on the sale of securities are recorded on the trade date and are determined using the specific identification method. Declines in the fair value of held to maturity and available for sale securities below their amortized cost deemed to be OTTI are written down to fair value as determined by a cash flow analysis. To the extent the estimated cash flows do not support the amortized cost, the deficiency is considered to be due to credit loss and recognized in earnings. Unless the Company intends to sell the security, or if it is more likely than not that the Company will be required to sell the debt security before its anticipated recovery, the remainder of the OTTI charge is considered to be due to other factors, such as liquidity or interest rates, and thus is not recognized in earnings, but rather through other comprehensive income, net of related tax. The Company evaluates individual securities that have fair values below cost for six months or longer, or for a shorter period of time if considered appropriate by management, to determine if the decline in fair value is other-than-temporary. Consideration is given to the obligor of the security, whether the security is guaranteed, whether there is a projected adverse change in cash flows, the liquidity of the security, the type of security, the capital position of security issuers, and payment history of the security, amongst other factors when evaluating such securities.
LOANS HELD FOR SALE	Loans Held for Sale The Bank primarily classifies new residential real estate mortgage loans as held for sale based on intent, which is determined when loans are underwritten. Residential real estate mortgage loans not designated as held for sale are retained based upon available liquidity, for interest rate risk management and other business purposes. The Company has elected the fair value option to account for originated closed loans intended for sale. Accordingly, changes in fair value relating to loans intended for sale are recorded in earnings and are offset by changes in fair value relating to interest rate lock commitments and forward sales commitments. Gains and losses on residential loan sales (sales proceeds minus carrying amount) are recorded in mortgage banking income. Upfront costs and fees related to items for which the fair value option is elected are recognized in earnings as incurred and are not deferred.
LOANS	Loans Loans are carried at the principal amounts outstanding, or fair value in the case of acquired loans, adjusted by partial charge-offs and net of deferred loan costs or fees. For originated loans, loan fees and certain direct origination costs are deferred and amortized into interest income over the expected term of the loan using the level-yield method. When a loan is paid off, the unamortized portion is recognized in interest income. Interest income on loans is accrued based upon the daily principal amount outstanding except for loans on nonaccrual status. For acquired loans which did not show signs of credit deterioration at acquisition, interest income is also accrued based upon the daily principal amount outstanding and is then further adjusted by the accretion of any discount or amortization of any premium associated with the loan. As a general rule, loans more than 90 days past due with respect to principal or interest are classified as nonaccrual loans, or sooner if management considers such action to be prudent. However, loans that are more than 90 days past due may be kept on an accruing status if the loan is well secured and in the process of collection. The Company may also put a junior lien mortgage on nonaccrual status as a result of delinquency with respect to the first position, which is held by the Bank or by another financial institution, while the junior lien is currently performing. Income accruals are suspended on all nonaccrual loans and all previously accrued and uncollected interest is reversed against current income. A loan remains on nonaccrual status until it becomes current with respect to principal and interest (and in certain instances remains current for up to six months), the loan is liquidated, or when the loan is determined to be uncollectible and is charged-off against the allowance for loan losses. When doubt exists as to the collectability of a loan, any payments received are applied to reduce the recorded investment in the asset to the extent necessary to eliminate such doubt. For all loan portfolios, a charge-off occurs when the Company determines that a specific loan, or portion thereof, is uncollectible. This determination is made based on management's review of specific facts and circumstances of the individual loan, including assessing the viability of the customer’s business or project as a going concern, the expected cash flows to repay the loan, the value of the collateral and the ability and willingness of any guarantors to perform.
ACQUIRED LOANS	Acquired loans All acquired loans are recorded at fair value with no carryover of the allowance for loan losses. At acquisition, loans are also reviewed to determine if the loan has evidence of deterioration in credit quality and to review if it is probable, at acquisition, that all contractually required payments will not be collected. Such loans are deemed to be purchased credit impaired ("PCI") loans. Under the accounting model for PCI loans, the excess of cash flows expected to be collected over the carrying amount of the loans, referred to as the "accretable yield", is accreted into interest income over the life of the loans using the effective yield method. Accordingly, PCI loans are not subject to classification as nonaccrual in the same manner as originated loans. Rather, acquired PCI loans are generally considered to be accruing loans because their interest income relates to the accretable yield recognized and not to contractual interest payments at the loan level. The difference between contractually required principal and interest payments and the cash flows expected to be collected, referred to as the "nonaccretable difference", includes estimates of both the impact of prepayments and future credit losses expected to be incurred over the life of the loans. The estimate of cash flows expected to be collected is regularly re-assessed subsequent to acquisition. These re-assessments involve updates, as necessary, of the key assumptions and estimates used in the initial estimate of fair value. Generally speaking, expected cash flows are affected by: • Changes in the expected principal and interest payments over the estimated life - Changes in expected cash flows may be driven by the credit outlook and actions taken with borrowers. Changes in expected future cash flows resulting from loan modifications are included in the assessment of expected cash flows. • Change in prepayment assumptions - Prepayments affect the estimated life of the loans, which may change the amount of interest income expected to be collected. • Change in interest rate indices for variable rate loans - Expected future cash flows are based, as applicable, on the variable rates in effect at the time of the assessment of expected cash flows. A decrease in expected cash flows in subsequent periods may indicate that the loan is impaired which would likely require the recognition of a charge-off against the allowance for loan losses or an establishment of a specific reserve. An increase in expected cash flows in subsequent periods serves, first, to reduce any previously established specific reserve by the increase in the present value of cash flows expected to be collected. Any increase above the previously established specific reserve results in a recalculation of the amount of accretable yield for the loan. The adjustment of accretable yield due to an increase in expected cash flows is accounted for as a change in estimate. The additional cash flows expected to be collected are reclassified from the nonaccretable difference to the accretable yield, and the amount of periodic accretion is adjusted accordingly over the remaining life of the loans. A PCI loan may be resolved either through receipt of payment (in full or in part) from the borrower, the sale of the loan to a third party, or foreclosure of the collateral. In the event of a sale of the loan, a gain or loss on sale would be recognized and reported within noninterest income based on the difference between the sales proceeds and the carrying amount of the loan. For PCI loans accounted for on an individual loan basis and resolved directly with the borrower, any amount received from resolution in excess of the carrying amount of the loan is recognized and reported within interest income. A refinancing or modification of a PCI loan accounted for individually is assessed to determine whether the modification represents a TDR. If the loan is considered to be a TDR, it will be included in the total impaired loans reported by the Company. The loan will continue to recognize interest income based upon the excess of cash flows expected to be collected over the carrying amount of the loan.
ALLOWANCE FOR LOAN LOSSES	Allowance for Loan Losses The allowance for loan losses is established based upon the level of estimated probable losses in the current loan portfolio. Loan losses are charged against the allowance when management believes the collectability of a loan balance is doubtful. Subsequent recoveries, if any, are credited to the allowance. The allowance for loan losses is allocated to loan types using both a formula-based approach applied to groups of loans and an analysis of certain individual loans for impairment. The formula-based approach emphasizes loss factors derived from actual historical portfolio loss rates, which are combined with an assessment of certain qualitative factors to determine the allowance amounts allocated to the various loan categories. Allowance amounts are determined based on an estimate of the historical average annual percentage rate of loan loss for each loan category, an estimate of the incurred loss emergence and confirmation period for each loan category, and certain qualitative risk factors considered in the computation of the allowance for loan losses. The qualitative risk factors impacting the inherent risk of loss within the portfolio include the following: • National and local economic and business conditions • Level and trend of delinquencies • Level and trend of charge-offs and recoveries • Trends in volume and terms of loans • Risk selection, lending policy and underwriting standards • Experience and depth of management • Banking industry conditions and other external factors • Concentration risk The formula-based approach evaluates groups of loans with common characteristics, which consist of similar loan types with similar terms and conditions, to determine the appropriate allocation within each portfolio section. This approach incorporates qualitative adjustments based upon management’s assessment of various market and portfolio specific risk factors into its formula-based estimate. Due to the imprecise nature of the loan loss estimation process and ever changing conditions, the qualitative risk attributes may not adequately capture amounts of incurred loss in the formula-based loan loss components used to determine the Bank’s analysis of the appropriateness of the allowance for loan losses. The Bank evaluates certain loans within the commercial and industrial, commercial real estate, commercial construction and small business portfolios individually for specific impairment. A loan is considered impaired when, based on current information and events, it is probable that the Bank will be unable to collect the scheduled payments of principal or interest when due according to the contractual terms of the loan agreement. Factors considered by management in determining impairment include payment status, collateral value, contractual interest rates and the probability of collecting scheduled principal and interest payments when due. Loans that experience insignificant payment delays and payment shortfalls generally are not classified as impaired. Loans are selected for evaluation based upon a change in internal risk rating, occurrence of delinquency, loan classification, troubled debt restructuring or nonaccrual status. A specific allowance amount is allocated to an individual loan when such loan has been deemed impaired and when the amount of the probable loss is able to be estimated. Estimates of loss may be determined by the present value of anticipated future cash flows, the loan’s observable fair market value, or the fair value of the collateral, if the loan is collateral dependent. However, for collateral dependent loans, the amount of the recorded investment in a loan that exceeds the fair value of the collateral less costs to sell is charged-off against the allowance for loan losses in lieu of an allocation of a specific allowance amount when such an amount has been identified definitively as uncollectible. Large groups of small-balance homogeneous loans such as the residential real estate, residential construction, home equity and other consumer portfolios are collectively evaluated for impairment. As such, the Bank does not typically identify individual loans within these groupings as impaired loans for impairment evaluation and disclosure. However, the Bank evaluates all TDRs for impairment on an individual loan basis regardless of loan type. In the ordinary course of business, the Bank enters into commitments to extend credit, commercial letters of credit, and standby letters of credit. Such financial instruments are recorded in the financial statements when they become payable. The credit risk associated with these commitments is evaluated in a manner similar to the allowance for loan losses. The reserve for unfunded lending commitments is included in other liabilities in the balance sheet. At December 31, 2019 and 2018 , the reserve for unfunded loan commitments was $2.1 million and $1.3 million , respectively.
Transfers and Servicing of Financial Assets, Transfers of Financial Assets, Financings, Policy [Policy Text Block]	Transfers and Servicing of Financial Assets Transfers of financial assets are accounted for as sales when control over the assets has been surrendered. Control over transferred assets is deemed to be surrendered when (1) the assets have been isolated from the Company, (2) the transferee obtains the right (free of conditions that constrain it from taking advantage of that right) to pledge or exchange the transferred assets, and (3) the Company does not maintain effective control over the transferred assets through an agreement to repurchase them before their maturity. Loans held for sale are generally sold with servicing rights released, however if rights are retained, servicing assets are recognized as separate assets. Servicing rights are originally recorded at fair value within other assets, but subsequently are amortized in proportion to and over the period of estimated net servicing income, and are assessed for impairment at each reporting date. Fair value is based on market prices for comparable mortgage servicing contracts, when available, or alternatively, is based on a valuation model that calculates the present value of estimated future net servicing income. The valuation model incorporates assumptions that market participants would use in estimating future net servicing income, such as the cost to service, the discount rate, the custodial earnings rate, an inflation rate, ancillary income, prepayment speeds, default rates and losses. Impairment is determined by stratifying the rights based on predominant characteristics, such as interest rate, loan type and investor type. Impairment is recognized through a valuation allowance, to the extent that fair value is less than the capitalized amount. If the Company later determines that all or a portion of the impairment no longer exists, a reduction of the allowance may be recorded as an increase to income. Servicing fee income is recorded for fees earned for servicing loans for investors. The fees are based on a contractual percentage of the outstanding principal or a fixed amount per loan, and are recorded as income when earned. The amortization of mortgage servicing rights is recorded as a reduction of loan servicing fee income.
FEDERAL HOME LOAN BANK STOCK	Federal Home Loan Bank Stock The Company, as a member of the Federal Home Loan Bank ("FHLB") of Boston, is required to maintain an investment in capital stock of the FHLB. Based on redemption provisions, the stock has no quoted market value and is carried at cost. The Company continually reviews its investment to determine if OTTI exists. The Company reviews recent public filings, rating agency analysis and other factors when making its determination.
BANK PREMISES AND EQUIPMENT	Bank Premises and Equipment Land is carried at cost. Bank premises and equipment are stated at cost less accumulated depreciation. Depreciation is computed using the straight-line convention method over the estimated useful lives of the assets. Leasehold improvements are amortized over the shorter of the lease terms or the estimated useful lives of the improvements. Expected terms include lease option periods to the extent that the exercise of such options is reasonably assured, not to exceed fifteen years .
GOODWILL AND IDENTIABLE INTANGIBLE ASSETS	Goodwill and Other Intangible Assets Goodwill represents the excess of the purchase price over the net fair value of acquired businesses. Goodwill is not amortized and is assigned to one reporting unit. Goodwill is evaluated for impairment at least annually, or more often if warranted, using a combined qualitative and quantitative impairment approach. The initial qualitative approach assesses whether the existence of events or circumstances led to a determination that it is more likely than not that the fair value of a reporting unit is less than its carrying amount. If, after assessing the totality of events and circumstances, the Company determines it is more likely than not that the fair value is less than carrying value, the two step quantitative impairment test is performed. Step one of the quantitative impairment test compares book value to the fair value of the reporting unit. If step one is failed, a detailed step two analysis is performed, which involves measuring the excess of the fair value of the reporting unit, as determined in step one, over the aggregate fair value of the individual assets, liabilities, and identifiable intangibles as if the reporting unit was being acquired in a business combination. Other intangible assets subject to amortization consist of core deposit intangibles, noncompete agreements, customer lists and market-based favorable or unfavorable lease positions at time of acquisition, and are amortized over the estimated lives of the intangibles using a method that approximates the amount of economic benefits that are realized by the Company. Other intangible assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets may not be recoverable. The range of useful lives is as follows: Core deposit intangibles 10 years Noncompete agreement 1 year Customer Lists 12 years Leases 3-30 years The determination of which intangible assets have finite lives is subjective, as is the determination of the amortization period for such intangible assets.
IMPAIRMENT OF LONG-LIVED ASSETS OTHER THAN GOODWILL	Impairment of Long-Lived Assets Other Than Goodwill The Company reviews long-lived assets, including premises and equipment, for impairment whenever events or changes in business circumstances indicate that the remaining useful life may warrant revision or that the carrying amount of the long-lived asset may not be fully recoverable. The Company would perform an undiscounted cash flow analysis to determine if impairment exists. If impairment is determined to exist, any related impairment loss is calculated based on fair value. Impairment losses on assets to be disposed of, if any, are based on the estimated proceeds to be received, less costs of disposal.
CASH SURRENDER VALUE OF LIFE INSURANCE POLICIES	Cash Surrender Value of Life Insurance Policies Increases in the cash surrender value ("CSV") of life insurance policies, as well as benefits received net of any CSV, are recorded in other noninterest income, and are generally not subject to income taxes. The CSV of the policies is recorded as an asset of the Bank, with liabilities recognized for any split dollar arrangements associated with the policies. The Company reviews the financial strength of the insurance carriers prior to the purchase of life insurance policies and no less than annually thereafter. Regulatory requirements limit the total amount of CSV to be held with any individual carrier to 15% of Tier 1 capital (as defined for regulatory purposes) and the total CSV of all life insurance policies is limited to 25% of Tier 1 capital.
OTHER REAL ESTATE OWNED AND OTHER FORECLOSED ASSETS	and Other Foreclosed Assets Real estate properties and other assets, which have served as collateral to secure loans, are held for sale and are initially recorded at fair value less estimated costs to sell at the date control is established, resulting in a new cost basis. The amount by which the recorded investment in the loan exceeds the fair value (net of estimated costs to sell) of the foreclosed asset is charged to the allowance for loan losses. Subsequent declines in the fair value of the foreclosed asset below the new cost basis are recorded through the use of a valuation allowance. Subsequent increases in the fair value are recorded as reductions in the valuation allowance, but not below zero. Upon a sale of a foreclosed asset, any excess of the carrying value over the sale proceeds is recognized as a loss on sale. Any excess of sale proceeds over the carrying value of the foreclosed asset is first applied as a recovery to the valuation allowance, if any, with the remainder being recognized as a gain on sale. Operating expenses and changes in the valuation allowance relating to foreclosed assets are included in other noninterest expense.
Repurchase and Resale Agreements Policy [Policy Text Block]	Customer Repurchase Agreements In a security repurchase agreement transaction, the Company will generally sell a security, agreeing to repurchase either the same or substantially identical security on a specified later date, at a greater price than the original sales price. The difference between the sale price and purchase price is the cost of the proceeds, which is recorded as interest expense. The securities underlying the agreements are delivered to counterparties as security for the repurchase obligations. Since the securities are treated as collateral and the agreement does not qualify for a full transfer of effective control, the transactions do not meet the criteria to be classified as a sale, and are therefore considered a secured borrowing transaction for accounting purposes.
DERIVATIVES	Derivatives Derivative instruments are carried at fair value in the Company’s financial statements. The accounting for changes in the fair value of a derivative instrument is determined by whether it has been designated and qualifies as part of a hedging relationship, and further, by the type of hedging relationship. At the inception of a hedge, the Company documents certain items, including but not limited to the following: the relationship between hedging instruments and hedged items, the Company's risk management objectives, hedging strategies, and the evaluation of hedge transaction effectiveness. Documentation includes linking all derivatives designated as fair value or cash flow hedges to specific assets and liabilities on the balance sheet or to specific forecasted transactions. For those derivative instruments that are designated and qualify for special hedge accounting, the Company designates the hedging instrument, based upon the exposure being hedged, as either a fair value hedge or a cash flow hedge. For derivative instruments that are designated and qualify as a cash flow hedge (i.e., hedging the exposure to variability in expected future cash flows that is attributable to a particular risk), the effective portion of the gain or loss on the derivative instrument is reported as a component of other comprehensive income, net of related tax. The Company considers any economic mismatch between the hedging instrument and the hedged transaction in its ongoing assessment of hedge effectiveness. If the hedging instrument is not highly effective at achieving offsetting cash flows attributable to the revised contractually specified interest rate(s), hedge accounting will be discontinued. At that time, accumulated other comprehensive income would be frozen and amortized, as long as the forecasted transactions are still probable of occurring. For derivative instruments designated and qualifying as a fair value hedge (i.e., hedging the exposure to changes in the fair value of an asset or liability or an identified portion thereof that is attributable to the hedged risk), the gain or loss on the derivative instrument, as well as the offsetting gain or loss on the hedged item attributable to the hedged risk, are recognized in current earnings during the period of the change in fair values. Hedge accounting is discontinued prospectively when (1) a derivative is no longer highly effective in offsetting changes in the fair value or cash flow of a hedged item, (2) a derivative expires or is settled, (3) it is no longer likely that a forecasted transaction associated with the hedge will occur, or (4) it is determined that designation of a derivative as a hedge is no longer appropriate. To the extent the Company enters into new or re-designates existing hedging relationships, it is the Company's policy to include the Overnight Index Swap Rate in the spectrum of available benchmark interest rates for hedge accounting. For derivative instruments not designated as hedging instruments, such as loan level derivatives, foreign exchange contracts and mortgage derivatives, changes in fair value are recognized in other noninterest income during the period of change and are included in changes in other assets or other liabilities on the Company's consolidated statement of cash flows.
RETIREMENT PLANS	Retirement Plans The Company has various retirement plans in place for current and former employees, including postretirement benefit plans, supplemental executive retirement plans, frozen multiemployer pension plans, deferred compensation plans, as well as other benefits. The postretirement benefit plans and the supplemental executive retirement plans are unfunded and therefore have no plan assets. The actuarial cost method used to compute the benefit liabilities and related expense is the projected unit credit method. The projected benefit obligation is principally determined based on the present value of the projected benefit distributions at an assumed discount rate. The discount rate which is utilized is based on the investment yield of high quality corporate bonds available in the market place with maturities approximately equal to projected cash flows of future benefit payments as of the measurement date. Periodic benefit expense (or income) includes service costs and interest costs based on the assumed discount rate, amortization of prior service costs due to plan amendments and amortization of actuarial gains and losses. Service costs are included in salaries and employee benefits and all other costs are included in other noninterest expense. The amortization of actuarial gains and losses is determined using the 10% corridor minimum amortization approach and is taken over the average remaining future working lifetime of the plan participants. The underfunded status of the plans is recorded as a liability on the balance sheet. The multiemployer pension plans' assets are determined based on fair value, generally representing observable market prices. The actuarial cost method used to compute the pension liabilities and related expense is the unit credit method. The pension expense is equal to the plan contribution requirement of the Company for the plan year. In conjunction with the acquisition of Blue Hills Bancorp, Inc., parent of Blue Hills Bank (collectively "BHB") the Company acquired BHB's defined benefit pension plan, which is administered by the Savings Banks Employees Retirement Association. The Company accounts for the plan using an actuarial model that allocates pension costs over the service period of employees in the plan. The Company accounts for the over-funded or under-funded status of the plan as an asset or liability on its consolidated balance sheets and recognizes changes in the funded status that are not reflected in net periodic pension cost as other comprehensive income or loss. BHB amended its defined benefit pension plan in 2013 freezing the plan to new participants and subsequently amended the plan and froze it for all participants effective October 31, 2014. The Director Deferred Compensation and 401(k) Restoration plans allow directors and employees to invest their funds within a rabbi trust, including both Company stock and other investment alternatives offered by the plan. The plans do not permit diversification after initial election and therefore elections made to defer into Company stock result in both the investment and obligation recognized within Stockholders' Equity. Alternatively, investments not in Company stock are included in trading securities, with the correlating obligation classified as a liability.
STOCK-BASED COMPENSATION	The Company has obligations with various individuals related to certain post-retirement benefits. The obligations are based on the individual's service through retirement, with the associated cost recognized over the requisite service period. The accrual methodology results in an accrued amount at the full eligibility date equal to the then present value of all of the future benefits expected to be paid. Stock-Based Compensation
INCOME TAXES	Income Taxes Deferred income tax assets and liabilities are determined using the asset and liability (or balance sheet) method of accounting for income taxes. Under this method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. If current available information raises doubt as to the realization of the deferred tax assets, a valuation allowance is established. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in enacted tax rates is recognized in income in the period that includes the enactment date. Income taxes are allocated to each entity in the consolidated group based on its share of taxable income. Management exercises significant judgment in evaluating the amount and timing of recognition of the resulting tax liabilities and assets, including projections of future taxable income. Additionally, a liability for unrecognized tax benefits is recorded for uncertain tax positions taken by the Company on its tax returns for which there is less than a 50% likelihood of being recognized upon a tax examination. Tax credits generated from the New Markets Tax Credit program are reflected in earnings when realized for federal income tax purposes.
Low Income Housing Tax Credits Policy Text Block [Policy Text Block]	Low Income Housing Tax Credits The Company accounts for its investments in qualified affordable housing projects using the proportional amortization method. Under the proportional amortization method the Company amortizes the initial cost of the investment in proportion to the tax credits and other tax benefits received, and recognizes the net investment benefit as a component of income tax expense (benefit).
ASSETS UNDER ADMININSTRATION	Assets Under Administration Assets held in a fiduciary or agency capacity for customers are not included in the accompanying consolidated balance sheet, as such assets are not assets of the Company. Revenue from administrative and management activities associated with these assets is recorded on an accrual basis.
Extinguishment of Debt [Policy Text Block]	Extinguishment of Debt Upon extinguishment of an outstanding debt, the Company records the difference between the exit price and the net carrying amount of the debt as a gain or loss on the extinguishment. The gain or loss is recorded as a component of other noninterest income or other noninterest expense, respectively.
EARNINGS PER SHARE	Earnings Per Share Basic earnings per share is calculated using the two-class method. The two-class method is an earnings allocation formula under which earnings per share is calculated from common stock and participating securities according to dividends declared and participation rights in undistributed earnings. Under this method, all earnings distributed and undistributed, are allocated to participating securities and common shares based on their respective rights to receive dividends. Unvested share-based payment awards that contain nonforfeitable rights to dividends are considered participating securities, not subject to performance based measures (i.e. unvested time-vested restricted stock). Basic earnings per share is calculated by dividing net income by the weighted average number of common shares outstanding (inclusive of participating securities). Diluted earnings per share have been calculated in a manner similar to that of basic earnings per share except that the weighted average number of common shares outstanding is increased to include the number of additional common shares that would have been outstanding if all potentially dilutive common shares (such as those resulting from the exercise of stock options or the attainment of performance measures) were issued during the period, computed using the treasury stock method.
COMPREHENSIVE INCOME	Comprehensive Income Comprehensive income consists of net income and other comprehensive income. Other comprehensive income includes unrealized gains and losses on securities available for sale, unrealized losses related to factors other than credit on debt securities, if applicable, unrealized gains and losses on cash flow hedges, deferred gains on hedge accounting transactions, and changes in the funded status of the Company’s postretirement and supplemental retirement plans.
FAIR VALUE MEASUREMENTS	Fair Value Measurements In general, fair values of financial instruments are based upon quoted market prices, where available. If such quoted market prices are not available, fair value is based upon developed models that primarily use, as inputs, observable market-based parameters. Valuation adjustments may be made to ensure that financial instruments are recorded at fair value. These adjustments may include amounts to reflect counterparty credit quality and the Company’s creditworthiness, among other things, as well as unobservable parameters.
Lessee, Leases [Policy Text Block]	Leases The Company leases office space, space for ATM locations and certain branch locations under noncancelable operating leases, several of which have renewal options to extend lease terms. Upon commencement of a new lease, the Company will recognize a right of use ("ROU") asset and corresponding lease liability. The Company makes the decision on whether to renew an option to extend a lease by considering various factors. The Company will recognize an adjustment to its ROU asset and lease liability when lease agreements are amended and executed. The discount rate used in determining the present value of lease payments is based on the Company's incremental borrowing rate for borrowings with terms similar to each lease at commencement date. The Company has lease agreements with lease and non-lease components, which are generally accounted for separately. For real estate leases, non-lease components and other non-components, such as common area maintenance charges, real estate taxes, and insurance are not included in the measurement of the lease liability since they are generally able to be segregated. The Company has elected the short-term lease recognition exemption for all leases that qualify.
New Accounting Pronouncements, Policy [Policy Text Block]	Recent Accounting Standards Financial Accounting Standards Board ("FASB") Accounting Standards Codification ("ASC") Topic 326 "Financial Instruments - Credit Losses" Update No. 2016-13. Update No. 2016-13 was issued in June 2016 and has been amended three times by the FASB (collectively, the "Updates"). The purpose of the Updates is to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments and other commitments to extend credit held by a reporting entity at each reporting date. To achieve this objective, these updates replace the incurred loss impairment methodology in current GAAP with a methodology that reflects current expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. The Updates affect loans, debt securities, trade receivables, net investments in leases, off-balance sheet credit exposures, reinsurance receivables, and any other financial assets not excluded from the scope that have the contractual right to receive cash. The Company adopted Topic 326 on January 1, 2020 and is in the process of validating the new model used to quantify the estimate for the Allowance for Credit Losses and updating its policy documents and internal controls accordingly. FASB ASC Topic 350 "Intangibles - Goodwill and Other " Update No. 2017-04. Update No. 2017-04 simplifies the subsequent measurement of goodwill, by eliminating Step 2 for the goodwill impairment test. An entity is no longer required to determine goodwill impairment by calculating the implied fair value of goodwill by assigning the fair value of a reporting unit to all of its assets and liabilities as if that reporting unit has been acquired in a business combination. The Company adopted the standard on January 1, 2020 and the adoption did not have a material impact on the Company's consolidated financial position.

SUMMARY OF SIGNIFICANT ACCOUN_3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Schedule of Finite-Lived Intangible Asses Useful Lives	The range of useful lives is as follows: Core deposit intangibles 10 years Noncompete agreement 1 year Customer Lists 12 years Leases 3-30 years The determination of which intangible assets have finite lives is subjective, as is the determination of the amortization period for such intangible assets.

ACQUISITIONS (Tables)

ACQUISITIONS (Tables)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Purchased Credit Impaired Loans Associated with Acquisition [Table Text Block]	The following is a summary of these PCI loans associated with the acquisition as of the date acquired: As of April 1, 2019 (Dollars in thousands) Contractually required principal and interest at acquisition $ 14,849 Contractual cash flows not expected to be collected (5,717 ) Expected cash flows at acquisition 9,132 Interest component of expected cash flows (1,464 ) Basis in PCI loans at acquisition - estimated fair value $ 7,668
Schedule of Estimated Fair Value of Assets Acquired and Liabilities Assumed	The following table summarizes the estimated fair value of the assets acquired and liabilities assumed as of the date of the acquisition: Net Assets Acquired at Fair Value (Dollars in thousands) Assets Cash $ 56,331 Investments 196,937 Loans 2,073,714 Premises and equipment 24,253 Goodwill 250,101 Core deposit and other intangibles 19,870 Other assets 146,192 Total assets acquired 2,767,398 Liabilities Deposits 1,930,436 Borrowings 124,817 Other liabilities 50,857 Total liabilities assumed 2,106,110 Purchase price $ 661,288	The following table summarizes the estimated fair value of the assets acquired and liabilities assumed as of the date of the acquisition: Net Assets Acquired at Fair Value (Dollars in thousands) Assets Cash $ 6,743 Investments 25,358 Loans 293,498 Premises and equipment 1,904 Goodwill 24,299 Core deposit and other intangibles 8,588 Other assets 8,639 Total assets acquired 369,029 Liabilities Deposits 278,204 Borrowings 33,093 Other liabilities 1,609 Total liabilities assumed 312,906 Purchase price $ 56,123
Business Acquisition, Pro Forma Information [Table Text Block]	The selected pro forma financial information is presented for illustrative purposes only and is not necessarily indicative of the financial results of the combined companies had the acquisition actually been completed at the beginning of the period presented, nor does it indicate future results for any other interim or full-year period. Year Ended December 31 2019 2018 (Dollars in thousands) Net interest income after provision for loan losses $ 408,918 $ 371,264 Net income $ 129,385 $ 146,178	The selected pro forma financial information is presented for illustrative purposes only and is not necessarily indicative of the financial results of the combined companies had the acquisition actually been completed at the beginning of the periods presented, nor does it indicate future results for any other interim or full-year period. Years Ended December 31 2018 2017 Net interest income after provision for loan losses $ 304,049 $ 267,104 Net income 122,310 88,518

SECURITIES (Tables)

SECURITIES (Tables)	12 Months Ended
	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Schedule of Equity securities gains and losses [Table Text Block]	The following table represents a summary of the gains and losses that relates to equity securities for the periods indicated: Years Ended December 31 2019 2018 2017 Net gains (losses) recognized during the period on equity securities $ 1,566 $ (1,225 ) n/a Less: net gains recognized during the period on equity securities sold during the period 18 874 n/a Unrealized gains (losses) recognized during the reporting period on equity securities still held at the reporting date $ 1,548 $ (2,099 ) n/a
Schedule of Available-for-sale Securities and Held-to-maturity Securities	The following table presents a summary of the amortized cost, gross unrealized holding gains and losses and fair value of securities available for sale and securities held to maturity as of the dates indicated: December 31, 2019 December 31, 2018 Amortized Gross Gross Unrealized Fair Amortized Gross Gross Unrealized Fair (Dollars in thousands) Available for sale securities U.S. government agency securities $ 32,473 $ 642 $ — $ 33,115 $ 32,477 $ — $ (439 ) $ 32,038 Agency mortgage-backed securities 243,548 3,456 (4 ) 247,000 222,491 1,020 (3,406 ) 220,105 Agency collateralized mortgage obligations 87,305 1,225 (19 ) 88,511 138,149 197 (3,435 ) 134,911 State, county, and municipal securities 1,377 19 — 1,396 1,719 16 — 1,735 Single issuer trust preferred securities issued by banks 488 5 — 493 717 — (10 ) 707 Pooled trust preferred securities issued by banks and insurers 1,488 — (374 ) 1,114 1,678 — (349 ) 1,329 Small business administration pooled securities 54,024 771 — 54,795 53,317 — (1,390 ) 51,927 Total available for sale securities 420,703 6,118 (397 ) 426,424 450,548 1,233 (9,029 ) 442,752 Held to maturity securities U.S. government agency securities 12,874 123 — 12,997 — — — — U.S. treasury securities 4,032 21 — 4,053 1,004 11 — 1,015 Agency mortgage-backed securities 397,414 8,445 (57 ) 405,802 252,484 1,548 (3,104 ) 250,928 Agency collateralized mortgage obligations 293,662 4,501 (849 ) 297,314 332,775 869 (6,920 ) 326,724 Single issuer trust preferred securities issued by banks 1,500 — (10 ) 1,490 1,500 — (10 ) 1,490 Small business administration pooled securities 31,324 338 (55 ) 31,607 23,727 105 (349 ) 23,483 Total held to maturity securities 740,806 13,428 (971 ) 753,263 611,490 2,533 (10,383 ) 603,640 Total $ 1,161,509 $ 19,546 $ (1,368 ) $ 1,179,687 $ 1,062,038 $ 3,766 $ (19,412 ) $ 1,046,392
Schedule of Contractual Maturities of Securities	A schedule of the contractual maturities of securities available for sale and securities held to maturity as of December 31, 2019 is presented below: Due in one year or less Due after one year to five years Due after five to ten years Due after ten years Total Amortized Cost Fair Value Amortized Cost Fair Value Amortized Cost Fair Value Amortized Cost Fair Value Amortized Cost Fair Value (Dollars in thousands) Available for sale securities U.S. government agency securities $ 10,000 $ 10,003 $ 10,002 $ 10,154 $ 12,471 $ 12,958 $ — $ — $ 32,473 $ 33,115 Agency mortgage-backed securities — — 70,945 71,305 54,798 56,181 117,805 119,514 243,548 247,000 Agency collateralized mortgage obligations — — — — — — 87,305 88,511 87,305 88,511 State, county, and municipal securities — — 1,188 1,193 189 203 — — 1,377 1,396 Single issuer trust preferred securities issued by banks — — — — — — 488 493 488 493 Pooled trust preferred securities issued by banks and insurers — — — — — — 1,488 1,114 1,488 1,114 Small business administration pooled securities — — — — — — 54,024 54,795 54,024 54,795 Total available for sale securities $ 10,000 $ 10,003 $ 82,135 $ 82,652 $ 67,458 $ 69,342 $ 261,110 $ 264,427 $ 420,703 $ 426,424 Held to maturity securities U.S. government agency securities $ 4,962 $ 4,989 $ 7,912 $ 8,008 $ — $ — $ — $ — $ 12,874 $ 12,997 U.S. Treasury securities — — 4,032 4,053 — — — — 4,032 4,053 Agency mortgage-backed securities — — 10,812 10,818 35,656 36,151 350,946 358,833 397,414 405,802 Agency collateralized mortgage obligations — — — — — — 293,662 297,314 293,662 297,314 Single issuer trust preferred securities issued by banks — — — — 1,500 1,490 — — 1,500 1,490 Small business administration pooled securities — — — — — — 31,324 31,607 31,324 31,607 Total held to maturity securities 4,962 4,989 22,756 22,879 37,156 37,641 675,932 687,754 740,806 753,263 Total $ 14,962 $ 14,992 $ 104,891 $ 105,531 $ 104,614 $ 106,983 $ 937,042 $ 952,181 $ 1,161,509 $ 1,179,687
Schedule of Gross Unrealized Losses and Fair Value of Investments	December 31, 2019 Less than 12 months 12 months or longer Total Description of securities # of Fair Value Unrealized Fair Unrealized Fair Value Unrealized (Dollars in thousands) Agency mortgage-backed securities 12 $ 34,009 $ (59 ) $ 243 $ (2 ) $ 34,252 $ (61 ) Agency collateralized mortgage obligations 17 48,476 (215 ) 37,382 (653 ) 85,858 (868 ) Single issuer trust preferred securities issued by banks and insurers 1 — — 1,490 (10 ) 1,490 (10 ) Pooled trust preferred securities issued by banks and insurers 1 — — 1,114 (374 ) 1,114 (374 ) Small business administration pooled securities 1 7,349 (55 ) — — 7,349 (55 ) Total temporarily impaired securities 32 $ 89,834 $ (329 ) $ 40,229 $ (1,039 ) $ 130,063 $ (1,368 ) December 31, 2018 Less than 12 months 12 months or longer Total Description of securities # of Fair Value Unrealized Fair Unrealized Fair Value Unrealized (Dollars in thousands) U.S. government agency securities 3 $ 9,960 $ (43 ) $ 22,078 $ (396 ) $ 32,038 $ (439 ) Agency mortgage-backed securities 144 104,616 (1,363 ) 222,850 (5,147 ) 327,466 (6,510 ) Agency collateralized mortgage obligations 48 57,871 (398 ) 279,229 (9,957 ) 337,100 (10,355 ) Single issuer trust preferred securities issued by banks and insurers 2 2,197 (20 ) — — 2,197 (20 ) Pooled trust preferred securities issued by banks and insurers 1 — — 1,329 (349 ) 1,329 (349 ) Small business administration pooled securities 7 28,257 (662 ) 40,621 (1,077 ) 68,878 (1,739 ) Total temporarily impaired securities 205 $ 202,901 $ (2,486 ) $ 566,107 $ (16,926 ) $ 769,008 $ (19,412 )

LOANS, ALLOWANCE FOR LOAN LOS_2

LOANS, ALLOWANCE FOR LOAN LOSSES AND CREDIT QUALITY (Tables)	12 Months Ended
	Dec. 31, 2019
Loans, Allowance for Loan Losses and Credit Quality [Abstract]
Schedule of Allowance for Loan Losses	December 31, 2019 Commercial Commercial Commercial Small Residential Home Other Consumer Total (Dollars in thousands) Allowance for loan losses Beginning balance $ 15,760 $ 32,370 $ 5,158 $ 1,756 $ 3,219 $ 5,608 $ 422 $ 64,293 Charge-offs (244 ) (2,614 ) — (509 ) — (240 ) (1,598 ) (5,205 ) Recoveries 1,131 152 — 122 142 318 787 2,652 Provision (benefit) 947 3,027 895 377 79 (110 ) 785 6,000 Ending balance $ 17,594 $ 32,935 $ 6,053 $ 1,746 $ 3,440 $ 5,576 $ 396 $ 67,740 Ending balance: collectively evaluated for impairment $ 17,468 $ 32,887 $ 6,053 $ 1,738 $ 2,803 $ 5,420 $ 391 $ 66,760 Ending balance: individually evaluated for impairment $ 126 $ 48 $ — $ 8 $ 637 $ 156 $ 5 $ 980 Financing receivables ending balance: Collectively evaluated for impairment $ 1,370,580 $ 3,987,848 $ 547,293 $ 173,960 $ 1,571,848 $ 1,127,963 $ 29,663 $ 8,809,155 Individually evaluated for impairment 24,456 8,337 — 537 11,228 4,948 122 49,628 Purchased credit impaired loans — 6,174 — — 7,493 887 302 14,856 Total loans by group $ 1,395,036 $ 4,002,359 $ 547,293 $ 174,497 $ 1,590,569 $ 1,133,798 $ 30,087 $ 8,873,639 (1) December 31, 2018 Commercial Commercial Commercial Small Residential Home Other Consumer Total (Dollars in thousands) Allowance for loan losses Beginning balance $ 13,256 $ 31,453 $ 5,698 $ 1,577 $ 2,822 $ 5,390 $ 447 $ 60,643 Charge-offs (355 ) (82 ) — (372 ) (148 ) (293 ) (1,347 ) (2,597 ) Recoveries 182 188 — 46 12 156 888 1,472 Provision (benefit) 2,677 811 (540 ) 505 533 355 434 4,775 Ending balance $ 15,760 $ 32,370 $ 5,158 $ 1,756 $ 3,219 $ 5,608 $ 422 $ 64,293 Ending balance: collectively evaluated for impairment $ 15,753 $ 32,333 $ 5,158 $ 1,755 $ 2,357 $ 5,444 $ 414 $ 63,214 Ending balance: individually evaluated for impairment $ 7 $ 37 $ — $ 1 $ 862 $ 164 $ 8 $ 1,079 Financing receivables ending balance: Collectively evaluated for impairment $ 1,064,800 $ 3,235,418 $ 365,165 $ 164,135 $ 906,959 $ 1,085,961 $ 15,901 $ 6,838,339 Individually evaluated for impairment 28,829 10,839 — 541 12,706 5,948 197 59,060 Purchased credit impaired loans — 4,991 — — 3,629 175 — 8,795 Total loans by group $ 1,093,629 $ 3,251,248 $ 365,165 $ 164,676 $ 923,294 $ 1,092,084 $ 16,098 $ 6,906,194 (1) December 31, 2017 Commercial Commercial Commercial Small Residential Other Consumer Total (Dollars in thousands) Allowance for loan losses Beginning balance $ 16,921 $ 30,369 $ 4,522 $ 1,502 $ 2,621 $ 5,238 $ 393 $ 61,566 Charge-offs (3,891 ) (39 ) — (302 ) (207 ) (276 ) (1,494 ) (6,209 ) Recoveries 615 385 — 114 31 198 993 2,336 Provision (benefit) (389 ) 738 1,176 263 377 230 555 2,950 Ending balance $ 13,256 $ 31,453 $ 5,698 $ 1,577 $ 2,822 $ 5,390 $ 447 $ 60,643 Ending balance: collectively evaluated for impairment $ 13,246 $ 31,411 $ 5,698 $ 1,576 $ 1,815 $ 5,125 $ 430 $ 59,301 Ending balance: individually evaluated for impairment $ 10 $ 42 $ — $ 1 $ 1,007 $ 265 $ 17 $ 1,342 Financing receivables ending balance: Collectively evaluated for impairment $ 853,885 $ 3,093,945 $ 401,797 $ 131,667 $ 733,809 $ 1,045,053 $ 9,573 $ 6,269,729 Individually evaluated for impairment 34,643 16,638 — 703 13,684 6,826 307 72,801 Purchase credit impaired loans — 5,978 — — 6,836 209 — 13,023 Total loans by group $ 888,528 $ 3,116,561 $ 401,797 $ 132,370 $ 754,329 $ 1,052,088 $ 9,880 $ 6,355,553 (1) (1) The amount of net deferred costs on originated loans included in the ending balance was $7.1 million , at December 31, 2019 and 2018 and $6.1 million and at December 31, 2017 . Net unamortized discounts on acquired loans not deemed to be PCI included in the ending balance were $21.6 million , $15.2 million and $9.4 million at December 31, 2019 , 2018 and 2017
Schedule of Internal Risk-Rating Categories for the Company's Commercial Portfolio	December 31, 2019 Category Risk Commercial and Commercial Real Commercial Small Business Total (Dollars in thousands) Pass 1 - 6 $ 1,274,155 $ 3,860,555 $ 542,608 $ 171,213 $ 5,848,531 Potential weakness 7 63,485 97,268 2,247 1,416 164,416 Definite weakness - loss unlikely 8 57,396 44,536 2,438 1,868 106,238 Partial loss probable 9 — — — — — Definite loss 10 — — — — — Total $ 1,395,036 $ 4,002,359 $ 547,293 $ 174,497 $ 6,119,185 December 31, 2018 Category Risk Commercial and Commercial Real Commercial Small Business Total (Dollars in thousands) Pass 1 - 6 $ 1,014,370 $ 3,156,989 $ 361,884 $ 161,851 $ 4,695,094 Potential weakness 7 16,860 56,840 298 888 74,886 Definite weakness - loss unlikely 8 58,909 37,419 2,983 1,937 101,248 Partial loss probable 9 3,490 — — — 3,490 Definite loss 10 — — — — — Total $ 1,093,629 $ 3,251,248 $ 365,165 $ 164,676 $ 4,874,718
Schedule of Weighted Average FICO Scores and Weighted Average Combined LTV Ratio	December 31 2019 2018 Residential portfolio FICO score (re-scored) (1) 749 749 LTV (re-valued) (2) 59.0 % 58.6 % Home equity portfolio FICO score (re-scored) (1) 767 767 LTV (re-valued) (2) (3) 46.6 % 49.3 % (1) The average FICO scores are based upon rescores available from November and origination score data for loans booked in December. (2) The combined LTV ratios are based upon updated automated valuations as of November, when available, and/or the most current valuation data available. The updated automated valuations provide new information on loans that may be available since the previous valuation was obtained. If no new information is available, the valuation will default to the previously obtained data or most recent appraisal. (3) For home equity loans and lines in a subordinate lien, the LTV data represents a combined LTV, taking into account the senior lien data for loans and lines.
Schedule of Nonaccrual Loans	The following table shows the carrying value of nonaccrual loans at the dates indicated: December 31 2019 2018 (Dollars in thousands) Commercial and industrial $ 22,574 $ 26,310 Commercial real estate 3,016 3,015 Commercial construction — 311 Small business 311 235 Residential real estate 13,360 8,251 Home equity 6,570 7,278 Other consumer 61 13 Total nonaccrual loans (1) $ 45,892 $ 45,413 (1) Included in these amounts were $24.8 million and $29.3 million of nonaccruing TDRs at December 31, 2019 and 2018
Foreclosed Residential Real Estate Property [Table Text Block]	The following table shows information regarding foreclosed residential real estate property at the date indicated: December 31, 2019 December 31, 2018 (Dollars in thousands) Foreclosed residential real estate property held by the creditor $ — $ — Recorded investment in mortgage loans collateralized by residential real estate property that are in the process of foreclosure $ 3,294 $ 3,174
Schedule of the Age Analysis of Past Due Financing Receivables	The following table shows the age analysis of past due financing receivables as of the dates indicated: December 31, 2019 30-59 days 60-89 days 90 days or more Total Past Due Current Total Recorded Number Principal Number Principal Number Principal Number Principal (Dollars in thousands) Commercial and industrial 1 $ 253 2 $ 323 5 $ 760 8 $ 1,336 $ 1,393,700 $ 1,395,036 $ — Commercial real estate 7 1,690 1 194 8 2,038 16 3,922 3,998,437 4,002,359 218 (2) Commercial construction 1 560 — — — — 1 560 546,733 547,293 — Small business 11 837 3 15 6 115 20 967 173,530 174,497 — Residential real estate 17 2,237 17 3,055 38 7,020 72 12,312 1,578,257 1,590,569 1,652 (2) Home equity 23 1,689 8 524 40 3,854 71 6,067 1,127,731 1,133,798 265 (2) Other consumer (1) 387 245 12 44 16 32 415 321 29,766 30,087 22 Total 447 $ 7,511 43 $ 4,155 113 $ 13,819 603 $ 25,485 $ 8,848,154 $ 8,873,639 $ 2,157 December 31, 2018 30-59 days 60-89 days 90 days or more Total Past Due Current Total Recorded Number Principal Number Principal Number Principal Number Principal (Dollars in thousands) Commercial and industrial — $ — 4 $ 382 11 $ 26,311 15 $ 26,693 $ 1,066,936 $ 1,093,629 $ — Commercial real estate 9 1,627 — — 8 2,250 17 3,877 3,247,371 3,251,248 — Commercial construction 1 1,271 — — 1 311 2 1,582 363,583 365,165 — Small business 15 506 19 87 24 162 58 755 163,921 164,676 — Residential real estate 23 3,486 6 521 25 4,382 54 8,389 914,905 923,294 — Home equity 22 1,331 12 855 29 2,663 63 4,849 1,087,235 1,092,084 — Other consumer (1) 330 181 15 9 12 13 357 203 15,895 16,098 5 Total 400 $ 8,402 56 $ 1,854 110 $ 36,092 566 $ 46,348 $ 6,859,846 $ 6,906,194 $ 5 (1)
Schedule of Troubled Debt Restructuring and Other Pertinent Information	The following table shows the Company’s total TDRs and other pertinent information as of the dates indicated: December 31 2019 2018 (Dollars in thousands) TDRs on accrual status $ 19,599 $ 23,849 TDRs on nonaccrual status 24,766 29,348 Total TDRs $ 44,365 $ 53,197 Amount of specific reserves included in the allowance for loan loss associated with TDRs: $ 855 $ 1,079 Additional commitments to lend to a borrower who has been a party to a TDR: $ 63 $ 982
Schedule of Troubled Debt Restructuring Modifications	The following table shows the modifications which occurred during the periods indicated and the change in the recorded investment subsequent to the modifications occurring: Years Ended December 31 2019 Number Pre-Modification Post-Modification (Dollars in thousands) Troubled debt restructurings Commercial and industrial 3 $ 268 $ 268 Commercial real estate 4 819 819 Small business 1 14 14 Residential real estate 3 967 1,009 Home equity 2 121 121 Total 13 $ 2,189 $ 2,231 2018 Troubled debt restructurings Commercial and industrial (1) 12 $ 35,688 $ 39,224 Commercial real estate 3 1,600 1,600 Residential real estate 5 1,048 1,071 Home equity 9 562 562 Total 29 $ 38,898 $ 42,457 2017 Troubled debt restructurings Commercial and industrial 12 $ 1,787 $ 1,787 Commercial real estate 6 2,705 2,705 Small business 9 369 369 Residential real estate 10 1,284 1,326 Home equity 17 1,985 1,988 Total 54 $ 8,130 $ 8,175 (1)
Schedule of Post-Modification Balance of Troubled Debt Restructuring by Type of Modification	The following table shows the Company’s post-modification balance of TDRs listed by type of modification for the periods indicated: Years Ended December 31 2019 2018 2017 (Dollars in thousands) Extended maturity $ 1,565 $ 2,878 $ 5,881 Adjusted interest rate 150 57 — Combination rate and maturity 441 38,812 568 Court ordered concession 75 710 1,726 Total $ 2,231 $ 42,457 $ 8,175
Schedule of Troubled Debt Restructurings Which Have Subsequently Defaulted	The Company considers a loan to have defaulted when it reaches 90 days past due. As of December 31, 2019 and 2018, there were no loans modified during the prior twelve months that subsequently defaulted. During the twelve months ended December 31, 2017 there was one commercial and industrial loan that was modified during the proceeding twelve month period, with a recorded investment of 122,000 , which subsequently defaulted.
Schedule of Impaired Loans by Loan Portfolio	The tables below set forth information regarding the Company’s impaired loans. The information for average recorded investment and interest income recognized is reflective of the full period being presented and does not take into account the date at which a loan was deemed to be impaired. See information below as of the dates indicated: As of and For the Years Ended December 31 2019 Recorded Unpaid Related Average Interest Income Recognized (Dollars in thousands) With no related allowance recorded Commercial and industrial $ 23,786 $ 34,970 $ — $ 27,056 $ 136 Commercial real estate 6,213 12,101 — 12,595 523 Small business 469 484 — 471 22 Residential real estate 4,976 5,123 — 5,045 222 Home equity 3,764 3,893 — 3,869 184 Other consumer 34 34 — 41 3 Subtotal 39,242 56,605 — 49,077 1,090 With an allowance recorded Commercial and industrial 670 670 126 718 29 Commercial real estate 2,124 2,124 48 2,176 122 Small business 68 105 8 74 2 Residential real estate 6,252 7,163 637 6,326 239 Home equity 1,184 1,382 156 1,214 52 Other consumer 88 91 5 97 3 Subtotal 10,386 11,535 980 10,605 447 Total $ 49,628 $ 68,140 $ 980 $ 59,682 $ 1,537 2018 Recorded Unpaid Related Average Interest (Dollars in thousands) With no related allowance recorded Commercial and industrial $ 28,459 $ 35,913 $ — $ 31,117 $ 142 Commercial real estate 9,552 9,832 — 10,561 519 Small business 358 439 — 401 14 Residential real estate 4,518 4,686 — 4,597 212 Home equity 4,957 5,199 — 5,230 220 Other consumer 56 56 — 64 4 Subtotal 47,900 56,125 — 51,970 1,111 With an allowance recorded Commercial and industrial 370 370 7 385 19 Commercial real estate 1,287 1,287 37 1,311 74 Small business 183 223 1 225 13 Residential real estate 8,188 9,217 862 8,459 289 Home equity 991 1,149 164 1,018 43 Other consumer 141 143 8 154 5 Subtotal 11,160 12,389 1,079 11,552 443 Total $ 59,060 $ 68,514 $ 1,079 $ 63,522 $ 1,554 2017 Recorded Unpaid Related Average Interest (Dollars in thousands) With no related allowance recorded Commercial and industrial $ 34,267 $ 38,329 $ — $ 36,631 $ 446 Commercial real estate 13,245 14,374 — 13,683 559 Small business 556 619 — 569 21 Residential real estate 4,264 4,397 — 4,332 218 Home equity 4,950 5,056 — 5,063 198 Other consumer 91 92 — 102 7 Subtotal 57,373 62,867 — 60,380 1,449 With an allowance recorded Commercial and industrial 376 376 10 391 19 Commercial real estate 3,393 3,399 42 3,447 198 Small business 147 153 1 238 14 Residential real estate 9,420 10,154 1,007 9,575 284 Home equity 1,876 2,110 265 1,916 55 Other consumer 216 217 17 233 7 Subtotal 15,428 16,409 1,342 15,800 577 Total $ 72,801 $ 79,276 $ 1,342 $ 76,180 $ 2,026
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Table Text Block]	December 31 2019 2018 (Dollars in thousands) Outstanding balance $ 18,358 $ 9,749 Carrying amount $ 14,856 $ 8,795
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Table Text Block]	The following table summarizes activity in the accretable yield for the PCI loan portfolio: 2019 2018 (Dollars in thousands) Beginning balance $ 1,191 $ 1,791 Acquisition 1,464 — Accretion (1,751 ) (1,135 ) Other change in expected cash flows (1) 803 310 Reclassification from nonaccretable difference for loans which have paid off (2) 227 225 Ending balance $ 1,934 $ 1,191 (1) Represents changes in cash flows expected to be collected resulting in increased interest income as a prospective yield adjustment over the remaining life of the loan(s). (2)

BANK PREMISES AND EQUIPMENT (Ta

BANK PREMISES AND EQUIPMENT (Tables)	12 Months Ended
	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Schedule of Premises and Equipment	Bank premises and equipment at December 31, were as follows: 2019 2018 Estimated (Dollars in thousands) (In years) Cost Land $ 32,619 $ 24,502 n/a Bank premises 62,455 53,052 5-40 Leasehold improvements 35,498 27,615 1-27 Furniture and equipment 77,705 66,974 2-12 Leased equipment 10,644 10,644 7 Total cost 218,921 182,787 Accumulated depreciation (95,247 ) (85,206 ) Net bank premises and equipment $ 123,674 $ 97,581

GOODWILL AND IDENTIFIABLE INT_2

GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS (Tables)	12 Months Ended
	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Intangible Assets and Goodwill	The following table sets forth the carrying value of goodwill and other intangible assets, net of accumulated amortization, at December 31: 2019 2018 (Dollars in thousands) Balances not subject to amortization Goodwill $ 506,206 $ 256,105 Balances subject to amortization Core deposit intangibles 28,016 13,692 Other intangible assets 1,270 1,558 Total other intangible assets 29,286 15,250 Total goodwill and other intangible assets $ 535,492 $ 271,355
Schedule of Goodwill	The changes in the carrying value of goodwill for the periods indicated were as follows: 2019 2018 (Dollars in thousands) Balance at beginning of year $ 256,105 $ 231,806 Acquisitions 250,101 24,299 Balance at end of year $ 506,206 $ 256,105
Schedule of Other Intangible Assets	The gross carrying amount and accumulated amortization of other intangible assets were as follows at the dates indicated: December 31 2019 2018 Gross Accumulated Net Gross Accumulated Net (Dollars in thousands) Core deposit intangibles $ 45,245 $ (17,229 ) $ 28,016 $ 34,137 $ (20,445 ) $ 13,692 Other intangible assets 3,338 (2,068 ) 1,270 3,103 (1,545 ) 1,558 Total $ 48,583 $ (19,297 ) $ 29,286 $ 37,240 $ (21,990 ) $ 15,250
Schedule of Intangible Assets Estimated Annual Amortization Expense	The following table sets forth the estimated annual amortization expense of intangible assets for each of the next five years: Year Amount (Dollars in thousands) 2020 $ 6,179 2021 $ 5,315 2022 $ 4,539 2023 $ 3,948 2024 $ 3,162

DEPOSITS (Tables)

DEPOSITS (Tables)	12 Months Ended
	Dec. 31, 2019
Banking and Thrift [Abstract]
Schedule of Time Deposits Maturities	The following is a summary of the scheduled maturities of time deposits as of December 31: 2019 2018 (Dollars in thousands) 1 year or less $ 1,097,407 78.6 % $ 511,292 71.9 % Over 1 year to 2 years 204,690 14.7 % 111,487 15.7 % Over 2 years to 3 years 55,615 4.0 % 41,523 5.8 % Over 3 years to 4 years 24,038 1.7 % 27,040 3.8 % Over 4 years to 5 years 13,565 1.0 % 19,761 2.8 % Total $ 1,395,315 100.0 % $ 711,103 100.0 %

BORROWINGS (Tables)

BORROWINGS (Tables)	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
Schedule of Federal Home Loan Bank Borrowings	Advances payable to the Federal Home Loan Bank as of December 31 of the years below are summarized as follows: 2019 2018 Weighted Weighted Average Average Total Contractual Total Contractual Outstanding Rate Outstanding Rate (Dollars in thousands) Stated Maturity 2019 $ — — % $ 147,046 2.68 % 2020 104,976 1.79 % — — % 2021 10,042 2.95 % — — % Subtotal 115,018 1.89 % 147,046 2.68 % Amortizing advances 730 760 Total Federal Home Loan Bank Advances $ 115,748 $ 147,806
Schedule of Long-term Borrowings	The following table summarizes long-term debt, net of debt issuances costs, as of the dates indicated: December 31 2019 2018 (Dollars in thousands) Long term borrowings, net $ 74,906 $ — Junior subordinated debentures Capital Trust V 51,507 51,505 Slades Ferry Trust I — 10,234 Central Trust I 5,258 5,258 Central Trust II 6,083 6,083 East Main Street Trust — 3,093 Subordinated debentures 49,601 34,728 Total long-term debt $ 187,355 $ 110,901
Information relating to Trust Preferred Securities [Table Text Block]	Information relating to these trust preferred securities is as follows: Trust Description of Capital Securities Capital Trust V $50.0 million due in 2037, interest at a variable rate of 3 month LIBOR plus 1.48% (3.37% at December 31, 2019),which, effective on January 17, 2017, has been converted to a fixed rate of 2.84% through the use of an interest rate swap. Central Trust I $5.1 million due in 2034, bearing interest at a variable rate of 3 month LIBOR plus 2.44% (4.33% at December 31, 2019). These securities are callable quarterly, until maturity. Central Trust II $5.9 million due in 2037, bearing interest at a variable rate of 3 month LIBOR plus 1.65% (3.54% at December 31, 2019). These securities are callable quarterly, until maturity.
Schedule of Maturities of Borrowings	The following table sets forth the contractual maturities of long-term debt over the next five years: 2020 2021 2022 2023 2024 Thereafter Total (Dollars in thousands) Long term borrowings $ — $ — $ 75,000 $ — $ — $ — $ 75,000 Junior subordinated debentures Capital trust V — — — — — 51,547 51,547 Central trust I — — — — — 5,258 5,258 Central trust II — — — — — 6,083 6,083 Subordinated debentures — — — — — 50,000 50,000 Total (1) $ — $ — $ 75,000 $ — $ — $ 112,888 $ 187,888 (1) Amounts in this table are presented on a gross basis, and do not include the capitalized issuance costs as presented in the Company's Consolidated Balance Sheet.

EARNINGS PER SHARE (Tables)

EARNINGS PER SHARE (Tables)	12 Months Ended
	Dec. 31, 2019
Earnings Per Share [Abstract]
Schedule of the Components of Earnings Per Share	Earnings per share consisted of the following components for the years ended December 31: 2019 2018 2017 (Dollars in thousands, except per share data) Net income $ 165,175 $ 121,622 $ 87,204 Weighted Average Shares Basic shares 32,810,433 27,592,380 27,294,028 Effect of dilutive securities 45,801 61,428 78,076 Diluted shares 32,856,234 27,653,808 27,372,104 Net income per share Basic EPS $ 5.03 $ 4.41 $ 3.19 Effect of dilutive securities — (0.01 ) — Diluted EPS $ 5.03 $ 4.40 $ 3.19

STOCK BASED COMPENSATION (Table

STOCK BASED COMPENSATION (Tables)	12 Months Ended
	Dec. 31, 2019
Share-based Payment Arrangement [Abstract]
Schedule of Cumulatively Granted Stock Options and Restricted Stock Awards, Net of Forfeitures and Expirations	The following table presents the amount of cumulatively granted stock option awards and restricted stock awards, net of forfeitures and expirations, granted through December 31, 2019 : Authorized Awards Cumulatively Granted, Net of Total Authorized Stock Restricted 2005 Plan 1,650,000 387,258 810,381 1,197,639 452,361 2010 Plan 314,600 46,500 93,245 139,745 — (1) 2018 Plan 300,000 — 12,500 12,500 287,500 (1) (1) The Company may award up to a total of 300,000 shares from the 2018 Plan, inclusive of 174,855 shares that were Authorized but Unissued in the 2010 Plan, and were transferred from the 2010 Plan to the 2018 Plan. Due to this transfer, there are no available shares remaining to be issued from the 2010 Plan.
Schedule of Pre-tax Compensation Expense and Related Tax Benefits	The following table presents the pre-tax expense associated with stock option and restricted stock awards and the related tax benefits recognized for the periods presented: Years Ended December 31 2019 2018 2017 (Dollars in thousands) Stock based compensation expense Restricted stock awards (1) $ 3,679 $ 3,299 $ 2,730 Directors’ fee expense (2) Stock options 23 66 76 Restricted stock awards 701 860 527 Total stock based award expense $ 4,403 $ 4,225 $ 3,333 Related tax benefits recognized in earnings $ 1,238 $ 1,188 $ 1,362 (1) Inclusive of compensation expense associated with time-vested and performance-based restricted stock awards. (2) Expense related to awards issued to directors is recognized as directors’ fees within other noninterest expense.
Schedule of Stock Options Granted	The following table presents the awards granted by the Company of nonqualified options to purchase shares of common stock for the periods presented: Years Ended December 31 2018 2017 Date of grant 4/3/2018 11/7/2017 Plan 2010 2010 Options granted 5,000 5,000 Vesting period (beginning on the grant date) 21 months 14 months Expiration date 4/3/2028 11/7/2027 Expected volatility 21.15 % 20.80 % Expected life (years) 5.5 5.5 Expected dividend yield 1.94 % 1.87 % Risk free interest rate 2.62 % 2.02 % Fair value per option $ 13.46 $ 12.43
Schedule of Relevant Information Relating to Stock Options	The following table presents relevant information relating to the Company’s stock options for the periods presented: Years Ended December 31 2019 2018 2017 (Dollars in thousands, except per share data) Fair value of stock options vested based on grant date fair value $ 21 $ 85 $ 72 Intrinsic value of stock options exercised $ 883 $ 1,525 $ 1,082 Cash received from stock option exercises $ 396 $ 1,024 $ 918 Tax benefit realized on stock option exercises $ 248 $ 429 $ 442 Weighted average grant date fair value of options granted (per share) n/a $ 13.46 $ 12.43
Schedule of Stock Options	The following table presents a summary of stock option award activity for the year ended December 31, 2019 . Outstanding Nonvested Stock Option Weighted Weighted Aggregate Stock Weighted (Dollars in thousands, except per share data) Balance at January 1, 2019 54,500 $ 37.28 3,332 $ 12.94 Granted — — — — Exercised (16,000 ) 24.76 n/a n/a Vested n/a n/a (1,666 ) 12.43 Forfeited — — — — Expired — — — — Balance at December 31, 2019 38,500 (2) $ 42.49 4.00 years $ 1,584 1,666 $ 13.46 Options outstanding and expected to vest at December 31, 2019 38,500 (3) $ 42.49 4.00 years $ 1,584 Options exercisable at December 31, 2019 36,834 (4) $ 41.21 3.81 years $ 1,563 Unrecognized compensation cost $ — Weighted average remaining recognition period (years) 0.00 (1) The aggregate intrinsic value represents the total pre-tax intrinsic value, based on the average of the high price and low price at which the Company’s common stock traded on December 31, 2019 of $83.64 , which would have been received by in-the-money option holders had they all exercised their options as of that date. (2) Inclusive of 22,500 stock options outstanding to Directors. (3) Inclusive of 22,500 vested stock options and expected to vest to Directors. (4) Inclusive of 20,834 vested stock options outstanding to Directors.
Schedule of Restricted Stock Granted	During the years ended December 31, 2019 , 2018 , and 2017 the Company made the following restricted stock award grants: Shares Granted Plan Fair Value (1) Vesting Period Time-vested 2019 2/21/2019 43,250 2005 $ 83.87 Ratably over 5 years from grant date 3/15/2019 600 2005 $ 79.55 Ratably over 5 years from grant date 4/1/2019 1,090 2005 $ 82.62 Ratably over 3 years from grant date 5/21/2019 6,500 2018 $ 77.08 Immediately upon grant date 2018 2/15/2018 39,950 2005 $ 71.75 Ratably over 5 years from grant date 2/27/2018 1,150 2005 $ 72.60 Ratably over 5 years from grant date 5/15/2018 530 2005 $ 74.00 Ratably over 5 years from grant date 5/22/2018 6,000 2018 $ 76.58 Immediately upon grant date 11/15/2018 560 2005 $ 77.78 Ratably over 5 years from grant date 2017 2/13/2017 1,200 2005 $ 62.53 Ratably over 5 years from grant date 2/16/2017 34,150 2005 $ 63.10 Ratably over 5 years from grant date 3/31/2017 500 2005 $ 65.63 Ratably over 5 years from grant date 4/3/2017 1,500 2005 $ 64.14 Once on November 30, 2017 (2) 5/15/2017 1,000 2005 $ 64.03 Ratably over 5 years from grant date 5/23/2017 7,000 2010 $ 61.95 At the end of 5 years from grant date (3) 6/15/2017 950 2005 $ 66.18 Ratably over 5 years from grant date Performance-based 2/21/2019 15,900 2005 $ 83.87 The earlier of: the date on which it is determined if the performance goal has been achieved; or, March 31, 2022. 2/15/2018 16,300 2005 $ 71.75 The earlier of: the date on which it is determined if the performance goal has been achieved; or, March 31, 2021. 2/16/2017 14,400 2005 $ 63.10 The earlier of: the date on which it is determined if the performance goal has been achieved; or, March 31, 2020. (1) The fair value of the restricted stock awards are based upon the average of the high and low prices at which the Company’s common stock traded on the date of grant. The holders of time-vested restricted stock awards participate fully in the rewards of stock ownership of the Company, including voting and dividend rights. The holders of performance-based restricted stock awards do not participate in the rewards of stock ownership of the Company until vested. The holders of all restricted stock awards are not required to pay any consideration to the Company for the awards. (2) This restricted stock grant fully vested upon an employee's termination, on November 30, 2017. (3) These restricted stock grants will vest at the end of a five year period, or earlier if the director ceases to be a director for any reason other than cause, such as, for example, by retirement.
Schedule of Share-based Compensation, Fair Value of Restricted Stock Awards Vesting [Table Text Block]	The following table presents the fair value of restricted stock awards vesting during the periods presented: Years Ended December 31 2019 2018 2017 (Dollars in thousands) Fair value of restricted stock awards upon vesting $ 6,005 $ 6,277 $ 5,717
Schedule of Restricted Stock Awards	The following table presents a summary of restricted stock award activity for the year ended December 31, 2019 : Outstanding Restricted Stock Weighted Average (Dollars in thousands, except per share data) Balance at January 1, 2019 202,106 $ 55.62 Granted 67,340 83.16 Vested/released (74,272 ) 49.56 Forfeited (1,390 ) 64.76 Balance at December 31, 2019 193,784 (1) $ 67.48 Unrecognized compensation cost (inclusive of directors’ fees) $ 8,098 Weighted average remaining recognition period (years) 2.99 (1) Inclusive of 17,925 restricted stock awards outstanding to Directors.

DERIVATIVES AND HEDGING ACTIV_2

DERIVATIVES AND HEDGING ACTIVITIES (Tables)	12 Months Ended
	Dec. 31, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes	The following table reflects information about the Company’s derivative positions as of the dates indicated below for interest rate swaps which qualify as cash flow hedges for accounting purposes: December 31, 2019 Weighted Average Rate Notional Amount Weighted Average Maturity Current Pay Fixed Fair Value (in thousands) (in years) (in thousands) Interest rate swaps on borrowings $ 75,000 2.18 1.90 % 1.53 % $ 140 Current Rate Paid Receive Fixed Swap Rate Interest rate swaps on loans 450,000 3.66 1.76 % 2.37 % 12,907 Current Rate Paid Receive Fixed Swap Rate Cap - Floor Interest rate collars on loans 400,000 3.66 1.76 % 2.73% - 2.20% 9,896 Total $ 925,000 $ 22,943 December 31, 2018 Weighted Average Rate Notional Amount Weighted Average Maturity Current Pay Fixed Fair Value (in thousands) (in years) (in thousands) Interest rate swaps on borrowings $ 75,000 3.18 2.74 % 1.53 % $ 2,282 Current Rate Paid Receive Fixed Swap Rate Interest rate swaps on loans 250,000 4.52 2.57 % 2.67 % 2,938 Current Rate Paid Receive Fixed Swap Rate Cap - Floor Interest rate collars on loans 250,000 4.17 2.47 % 3.02% - 2.51% 3,344 Total $ 575,000 $ 8,564
Summary of customer related derivative positions, not designated as hedging	The following table reflects the Company’s customer related derivative positions as of the dates indicated below for those derivatives not designated as hedging: Number of Notional Amount Maturing Less than 1 year Less than 2 years Less than 3 years Less than 4 years Thereafter Total Fair Value December 31, 2019 (Dollars in thousands) Loan level swaps Receive fixed, pay variable 299 $ 156,690 $ 125,203 $ 85,603 $ 165,599 $ 1,044,315 $ 1,577,410 $ 48,596 Pay fixed, receive variable 290 $ 156,690 $ 125,203 $ 85,603 $ 165,599 $ 1,044,315 $ 1,577,410 $ (48,591 ) Foreign exchange contracts Buys foreign currency, sells U.S. currency 40 $ 91,434 $ — $ — $ — $ — $ 91,434 $ (81 ) Buys U.S. currency, sells foreign currency 40 $ 91,434 $ — $ — $ — $ — $ 91,434 $ 123 December 31, 2018 (Dollars in thousands) Loan level swaps Receive fixed, pay variable 235 $ 50,702 $ 124,222 $ 97,904 $ 47,308 $ 631,471 $ 951,607 $ (2,907 ) Pay fixed, receive variable 220 $ 50,702 $ 124,222 $ 97,904 $ 47,308 $ 631,471 $ 951,607 $ 2,903 Foreign exchange contracts Buys foreign currency, sells U.S. currency 27 $ 60,297 $ 3,505 $ — $ — $ — $ 63,802 $ (1,404 ) Buys U.S. currency, sells foreign currency 27 $ 60,297 $ 3,505 $ — $ — $ — $ 63,802 $ 1,434 (1) The Company may enter into one dealer swap agreement which offsets multiple commercial borrower swap agreements.
Fair value of derivative financial instruments as well as their classification on the balance sheet	Asset Derivatives (1) Liability Derivatives (2) Fair Value at Fair Value at Fair Value at Fair Value at December 31, 2019 December 31, 2018 December 31, 2019 December 31, 2018 (Dollars in thousands) Derivatives designated as hedges Interest rate derivatives $ 23,140 $ 8,955 $ 197 $ 391 Derivatives not designated as hedges Customer Related Positions: Loan level derivatives 52,374 15,580 52,369 15,584 Foreign exchange contracts 1,191 1,578 1,149 1,548 Mortgage Derivatives Interest rate lock commitments 1,680 91 — — Forward sale loan commitments — 106 12 — Forward sale hedge commitments — — 196 — 55,245 17,355 53,726 17,132 Total $ 78,385 $ 26,310 $ 53,923 $ 17,523 (1) All asset derivatives are located in other assets on the balance sheet. (2) All liability derivatives are located in other liabilities on the balance sheet.
Effect of derivative financial instruments included in OCI and current earnings	The table below presents the effect of the Company’s derivative financial instruments included in OCI and current earnings for the periods indicated: Years Ended December 31 2019 2018 2017 (Dollars in thousands) Derivatives designated as hedges Gain in OCI on derivatives (effective portion), net of tax $ 10,331 $ 4,829 $ 443 Gain (loss) reclassified from OCI into interest income or interest expense (effective portion) $ 2,346 $ 1,000 $ (441 ) Loss recognized in income on derivatives (ineffective portion and amount excluded from effectiveness testing) Interest expense $ — $ — $ — Other expense — — — Total $ — $ — $ — Derivatives not designated as hedges Changes in fair value of customer related positions Other income $ 39 $ 46 $ 6 Other expenses (18 ) (29 ) (21 ) Changes in fair value of mortgage derivatives Mortgage banking income 1,275 39 (39 ) Total $ 1,296 $ 56 $ (54 )

BALANCE SHEET OFFSETTING (Table

BALANCE SHEET OFFSETTING (Tables)	12 Months Ended
	Dec. 31, 2019
Offsetting [Abstract]
Financial Instruments Derivative Assets Liabilities and resell agreements net of amount not offset [Table Text Block]	BALANCE SHEET OFFSETTING The Company does not offset fair value amounts recognized for derivative instruments or repurchase agreements. The Company does net the amount recognized for the right to reclaim cash collateral against the obligation to return cash collateral arising from derivative instruments executed with the same counterparty under a master netting arrangement. Collateral legally required to be maintained at dealer banks by the Company is monitored and adjusted as necessary. The following tables present the Company's asset and liability derivative positions and the potential effect of netting arrangements on its financial position, as of the dates indicated: Gross Amounts Not Offset in the Statement of Financial Position Gross Amounts Recognized in the Statement of Financial Position Gross Amounts Offset in the Statement of Financial Position Net Amounts Presented in the Statement of Financial Position Financial Instruments (1) Collateral Pledged (Received) Net Amount December 31, 2019 (Dollars in thousands) Derivative Assets Interest rate swaps $ 23,140 $ — $ 23,140 $ 23,140 $ — $ — Loan level derivatives 52,374 — 52,374 1,742 — 50,632 Customer foreign exchange contracts 1,191 — 1,191 — — 1,191 $ 76,705 $ — $ 76,705 $ 24,882 $ — $ 51,823 Derivative Liabilities Interest rate swaps $ 197 $ — $ 197 $ — $ 197 $ — Loan level derivatives 52,369 — 52,369 24,882 25,296 2,191 Customer foreign exchange contracts 1,149 — 1,149 — — 1,149 $ 53,715 $ — $ 53,715 $ 24,882 $ 25,493 $ 3,340 (1) Reflects offsetting derivative positions with the same counterparty. Gross Amounts Not Offset in the Statement of Financial Position Gross Amounts Recognized in the Statement of Financial Position Gross Amounts Offset in the Statement of Financial Position Net Amounts Presented in the Statement of Financial Position Financial Instruments (1) Collateral Pledged (Received) Net Amount December 31, 2018 (Dollars in thousands) Derivative Assets Interest rate swaps $ 8,955 $ — $ 8,955 $ 391 $ (5,527 ) $ 3,037 Loan level derivatives 15,580 — 15,580 6,165 (3,001 ) 6,414 Customer foreign exchange contracts 1,578 — 1,578 — — 1,578 $ 26,113 $ — $ 26,113 $ 6,556 $ (8,528 ) $ 11,029 Derivative Liabilities Interest rate swaps $ 391 $ — $ 391 $ 391 $ — $ — Loan level derivatives 15,584 — 15,584 6,165 173 9,246 Customer foreign exchange contracts 1,548 — 1,548 — — 1,548 $ 17,523 $ — $ 17,523 $ 6,556 $ 173 $ 10,794 (1)

INCOME TAXES (Tables)

INCOME TAXES (Tables)	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Schedule of Components of Income Taxes	The provision for income taxes is comprised of the following components: Years Ended December 31 2019 2018 2017 (Dollars in thousands) Current expense Federal $ 27,980 $ 25,129 $ 28,852 State 14,359 13,672 9,278 Total current expense 42,339 38,801 38,130 Deferred expense (benefit) Federal 9,080 (3,080 ) 7,953 State 1,514 (1,417 ) 1,258 Total deferred expense (benefit) 10,594 (4,497 ) 9,211 Total expense $ 52,933 $ 34,304 $ 47,341
Schedule of Income Tax Rate Reconciliation	The difference between the statutory federal income tax rate and the effective income tax rate reported for the last three years is detailed below: Years Ended December 31 2019 2018 2017 (Dollars in thousands) Computed statutory federal income tax provision $ 45,803 21.00 % $ 32,744 21.00 % $ 47,091 35.00 % State taxes, net of federal tax benefit 12,262 5.63 % 9,633 6.18 % 6,817 5.07 % Merger and other related costs (non-deductible) 582 0.27 % 130 0.08 % 213 0.16 % Change in valuation allowance 17 0.01 % 49 0.03 % 31 0.02 % Revaluation of net deferred tax assets — — % — — % 1,895 1.41 % New Markets Tax Credits (2,675 ) (1.23 )% (3,960 ) (2.54 )% (3,960 ) (2.94 )% Increase in cash surrender value of life insurance (1,144 ) (0.52 )% (1,160 ) (0.74 )% (1,445 ) (1.07 )% Low Income Housing Project Investments (1,696 ) (0.78 )% (1,030 ) (0.66 )% (1,253 ) (0.93 )% Stock-based compensation (824 ) (0.38 )% (885 ) (0.57 )% (1,258 ) (0.94 )% Nontaxable interest, net (757 ) (0.35 )% (566 ) (0.36 )% (987 ) (0.73 )% Other, net 1,365 0.63 % (651 ) (0.42 )% 197 0.15 % Total expense $ 52,933 24.28 % $ 34,304 22.00 % $ 47,341 35.20 %
Schedule of Net Deferred Tax Asset	The tax-effected components of the net deferred tax asset at December 31 of the years presented were as follows: 2019 2018 (Dollars in thousands) Deferred tax assets Accrued expenses not deducted for tax purposes $ 13,855 $ 11,922 Allowance for loan losses 18,993 17,764 Employee and director equity compensation 1,708 1,636 Loan basis difference fair value adjustment 6,804 4,761 Net operating loss carry-forward 2,546 170 Net unrealized loss on securities available for sale — 1,850 Operating lease liability 16,393 — Other 1,311 1,561 Gross deferred tax assets $ 61,610 $ 39,664 Valuation allowance (187 ) (170 ) Total deferred tax assets net of valuation allowance $ 61,423 $ 39,494 Deferred tax liabilities Core deposit and other intangibles $ 5,802 $ 3,803 Deferred loan fees, net 4,944 4,759 Derivatives fair value adjustment 6,461 2,413 Fixed assets 8,194 5,259 Goodwill 10,645 10,388 Prepaid pension 3,487 3,483 Right of use asset 15,911 — Other 3,965 1,139 Gross deferred tax liabilities $ 59,409 $ 31,244 Total net deferred tax asset $ 2,014 $ 8,250
Reconciliation of Unrecognized Tax Benefits	The Company accounts for uncertainties in income taxes by providing a tax reserve for certain positions. The following is a reconciliation of the beginning and ending amount of unrecognized tax benefits: (Dollars in thousands) Balance at December 31, 2017 $ 142 Increase for current year tax positions 73 Balance at December 31, 2018 215 Reduction of tax positions for prior years (127 ) Increase for current year tax positions 444 Balance at December 31, 2019 $ 532

LOW INCOME HOUSING PROJECT IN_2

LOW INCOME HOUSING PROJECT INVESTMENTS Low Income Housing Project Investments (Tables)	12 Months Ended
	Dec. 31, 2019
Low Income Housing Project Investments [Abstract]
Investments in Low Income Housing Projects [Table Text Block]	The following table presents certain information related to the Company's investments in low income housing projects as of December 31 of the years presented: 2019 2018 2017 (Dollars in thousands) Original investment value $ 96,275 $ 50,232 $ 47,399 Current recorded investment $ 72,510 $ 33,681 $ 35,225 Unfunded liability obligation $ 34,967 $ 3,935 $ 4,536 Tax credits and benefits earned during the year $ 7,342 $ 5,407 $ 5,654 Amortization of investments during the year (1) $ 5,645 $ 4,377 $ 4,402 Net income tax benefit recognized during the year $ 1,696 $ 1,030 $ 1,253 (1) The 2017 amount is inclusive of $466,000 related to the revaluation of Low Income Housing tax credit investments as a result of the 2017 Tax Act.

EMPLOYEE BENEFIT PLANS (Tables)

EMPLOYEE BENEFIT PLANS (Tables)	12 Months Ended
	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Schedule of Expected Benefit Payments [Table Text Block]	Estimated future benefit payments for the BHB Plan are presented below: Amount (Dollars in thousands) 2020 $ 629 2021 $ 834 2022 $ 591 2023 $ 583 2024 $ 556 2025-2029 $ 2,867 Expected future benefit payments for the defined benefit supplemental executive retirement plans are presented below: Defined Benefit Supplemental Executive (Dollars in thousands) 2020 $ 472 2021 $ 466 2022 $ 458 2023 $ 571 2024 $ 1,220 2025-2029 $ 5,853
Schedule of Multiemployer Plan	Funding Status FIP/RP Status Surcharge Expiration Minimum EIN/Pension 2019 2018 Pentegra defined benefit plan for financial institutions 13-5645888/333 At least 80 percent At least 80 percent No No N/A $ —
Schedule of Multiemployer Plan Contributions	The Company’s contributions to the Pension Plans were as follows for the periods indicated: Required Contributions - Plan Year Allocation Cash Payment Future period funding 2019-2020 2018-2019 2017-2018 (Dollars in thousands) 2019 $ 2,063 $ — $ 2,063 $ — $ — 2018 $ 2,642 $ 2,000 $ — $ 642 $ — 2017 $ 6,432 $ 5,000 $ — $ — $ 1,432
Changes in Projected Benefit Obligations, Fair Value of Plan Assets, and Funded Status of Plan [Table Text Block]	Information pertaining to the BHB Plan at December 31, 2019 is as follows: Amount (Dollars in thousands) Change in plan assets: Fair value of plan assets at beginning of year $ 9,697 Actual return on plan assets 1,886 Employer contribution 505 Benefits paid (435 ) Fair value of plan assets at end of year $ 11,653 Change in benefit obligation: Benefit obligation at beginning of year 10,824 Interest cost 424 Actuarial loss 2,874 Benefits paid (435 ) Benefit obligation at end of year $ 13,687 Funded status and accrued liability at end of year $ (2,034 ) Accumulated benefit obligation at end of year $ 13,687
Schedule of Net Benefit Costs [Table Text Block]	Amount (Dollars in thousands) Interest cost $ 424 Expected return on plan assets (780 ) Amortization of net actuarial loss 327 Net period pension benefit $ (29 )
Defined Benefit Plan, Plan Assets, Allocation [Table Text Block]	The fair value of major categories of the BHB Plan assets as of December 31, 2019 are summarized below: Fair Value Measurements at Reporting Date Using Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) (Dollars in thousands) Collective funds $ 967 967 $ — $ — Equity securities 1,131 1,131 — — Mutual funds 3,628 3,628 — — Total investments in the fair value hierarchy $ 5,726 $ 5,726 $ — $ — Investments measured at net asset value (1) 5,927 $ 11,653 (1) Under the Fair Value Measurements and Disclosure Topic of the FASB ASC, certain investments that were measured at fair value at net asset value per share (or its equivalent) have not been classified in the fair value hierarchy.
Schedule of Supplemental Retirement Expense and Contributions Paid	The following table shows the defined benefit supplemental retirement expense, and the contributions paid to the plans which were used only to pay the current year benefits as of the dates indicated: 2019 2018 2017 (Dollars in thousands) Retirement expense $ 1,356 $ 1,683 $ 1,580 Contributions paid $ 486 $ 434 $ 367
Schedule of Supplemental Executive Retirement Plans	The following table illustrates the status of the defined benefit supplemental executive retirement plans at December 31 for the years presented: Defined Benefit Supplemental Executive 2019 2018 2017 (Dollars in thousands) Change in accumulated benefit obligation Benefit obligation at beginning of year $ 14,963 $ 15,749 $ 14,177 Service cost 433 459 423 Interest cost 601 533 547 Actuarial loss (gain) 1,850 (1,344 ) 969 Benefits paid (486 ) (434 ) (367 ) Benefit obligation at end of year $ 17,361 $ 14,963 $ 15,749 Change in plan assets Fair value of plan assets at beginning of year $ — $ — $ — Employer contribution 486 434 367 Benefits paid (486 ) (434 ) (367 ) Fair value of plan assets at end of year $ — $ — $ — Funded status at end of year $ (17,361 ) $ (14,963 ) $ (15,749 ) Assets — — — Liabilities (17,361 ) (14,963 ) (15,749 ) Funded status at end of year $ (17,361 ) $ (14,963 ) $ (15,749 ) Amounts recognized in accumulated other comprehensive income ("AOCI") Net loss $ 3,509 $ 1,705 $ 3,465 Prior service cost 494 770 1,047 Amounts recognized in AOCI $ 4,003 $ 2,475 $ 4,512 Information for plans with an accumulated benefit obligation in excess of plan assets Projected benefit obligation $ 17,361 $ 14,963 $ 15,749 Accumulated benefit obligation $ 17,361 $ 14,963 $ 15,749 Net periodic benefit cost Service cost $ 433 $ 459 $ 423 Interest cost 601 533 547 Amortization of prior service cost 276 276 276 Recognized net actuarial loss 46 415 334 Net periodic benefit cost $ 1,356 $ 1,683 $ 1,580 Amounts in accumulated other comprehensive income expected to be recognized in net periodic benefit cost over next fiscal year Net actuarial loss $ 471 $ 41 $ 415 Net prior service cost $ 276 $ 276 $ 276 Discount rate used for benefit obligation 2.00 - 3.04% 3.24 - 4.09% 2.48-3.45% Discount rate used for net periodic benefit cost 3.24 - 4.09% 2.48 - 3.45% 2.49-3.94% Rate of compensation increase n/a n/a n/a

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Schedule of Assets and Liabilities Measured at Fair Value on a Recurring and Nonrecurring Basis	Assets and liabilities measured at fair value on a recurring and nonrecurring basis were as follows as of the dates indicated: Fair Value Measurements at Reporting Date Using Balance Quoted Prices in Significant Other Significant December 31, 2019 (Dollars in thousands) Recurring fair value measurements Assets Trading securities $ 2,179 $ 2,179 $ — $ — Equity securities 21,261 21,261 — — Securities available for sale U.S. government agency securities 33,115 — 33,115 — Agency mortgage-backed securities 247,000 — 247,000 — Agency collateralized mortgage obligations 88,511 — 88,511 — State, county, and municipal securities 1,396 — 1,396 — Single issuer trust preferred securities issued by banks and insurers 493 — 493 — Pooled trust preferred securities issued by banks and insurers 1,114 — — 1,114 Small business administration pooled securities 54,795 — 54,795 — Loans held for sale 33,307 — 33,307 — Derivative instruments 78,385 — 78,385 — Liabilities Derivative instruments 53,923 — 53,923 — Total recurring fair value measurements $ 507,633 $ 23,440 $ 483,079 $ 1,114 Nonrecurring fair value measurements Assets Collateral dependent impaired loans $ 25,515 $ — $ — $ 25,515 Total nonrecurring fair value measurements $ 25,515 $ — $ — $ 25,515 Fair Value Measurements at Reporting Date Using Balance Quoted Prices in Significant Other Significant December 31, 2018 (Dollars in thousands) Recurring fair value measurements Assets Trading securities $ 1,504 $ 1,504 $ — $ — Equity securities 19,477 19,477 — — Securities available for sale U.S. government agency securities 32,038 — 32,038 — Agency mortgage-backed securities 220,105 — 220,105 — Agency collateralized mortgage obligations 134,911 — 134,911 — State, county, and municipal securities 1,735 — 1,735 — Single issuer trust preferred securities issued by banks and insurers 707 — 707 — Pooled trust preferred securities issued by banks and insurers 1,329 — — 1,329 Small business administration pooled securities 51,927 — 51,927 — Loans held for sale 6,431 — 6,431 — Derivative instruments 26,310 — 26,310 — Liabilities Derivative instruments 17,523 — 17,523 — Total recurring fair value measurements $ 478,951 $ 20,981 $ 456,641 $ 1,329 Nonrecurring fair value measurements: Assets Collateral dependent impaired loans $ 29,109 $ — $ — $ 29,109 Total nonrecurring fair value measurements $ 29,109 $ — $ — $ 29,109
Reconciliation of Assets on Recurring Basis Using Significant Unobservable Inputs	All assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) were valued using pricing models and discounted cash flow methodologies, as of December 31, 2019 , 2018 and 2017 . This reconciliation is presented in the table below for the periods indicated: 2019 2018 2017 (Dollars in thousands) Pooled Trust Preferred Securities Beginning balance $ 1,329 $ 1,640 $ 1,584 Gain and (losses) (realized/unrealized) Included in earnings — — — Included in other comprehensive income (26 ) 191 77 Settlements (189 ) (502 ) (21 ) Ending Balance $ 1,114 $ 1,329 $ 1,640
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]	The following table sets forth certain unobservable inputs regarding the Company's financial instruments that are classified as Level 3 as of December 31st of the years indicated: Valuation Technique Fair Value Unobservable Inputs Range Weighted Average 2019 2018 2019 2018 2019 2018 (Dollars in thousands) Discounted cash flow methodology Pooled trust preferred securities $ 1,114 $ 1,329 Cumulative prepayment 0% - 57% 0% - 59% 2.6% 2.1% Cumulative default 2% - 100% 5% - 100% 13.5% 16.2% Loss given default 85% - 100% 85% - 100% 93.6% 94.8% Cure given default 0% - 75% 0% - 75% 60.9% 60.9% Appraisals of collateral (1) Collateral dependent impaired loans $ 25,515 $ 29,109 (1) Fair value is generally determined through independent appraisals of the underlying collateral, which generally include various Level 3 inputs which are not identifiable. Appraisals may be adjusted by management for qualitative factors such as economic factors and estimated liquidation expenses. The range of these possible adjustments may vary.
Schedule of Fair Values and Related Carrying Amounts by Balance Sheet Grouping	he estimated fair values and related carrying amounts for assets and liabilities for which fair value is only disclosed are shown below as of the dates indicated: Fair Value Measurements at Reporting Date Using Carrying Value Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) December 31, 2019 (Dollars in thousands) Financial assets Securities held to maturity (a) U.S. government agency securities $ 12,874 $ 12,997 $ — $ 12,997 $ — U.S. Treasury securities 4,032 4,053 — 4,053 — Agency mortgage-backed securities 397,414 405,802 — 405,802 — Agency collateralized mortgage obligations 293,662 297,314 — 297,314 — Single issuer trust preferred securities issued by banks 1,500 1,490 — 1,490 — Small business administration pooled securities 31,324 31,607 — 31,607 — Loans, net of allowance for loan losses (b) 8,780,384 8,613,635 — — 8,613,635 Federal Home Loan Bank stock (c) 14,424 14,424 — 14,424 — Cash surrender value of life insurance policies (d) 197,372 197,372 — 197,372 — Financial liabilities Deposit liabilities, other than time deposits (e) $ 7,752,052 $ 7,752,052 $ — $ 7,752,052 $ — Time certificates of deposits (f) 1,395,315 1,396,760 — 1,396,760 — Federal Home Loan Bank borrowings (f) 115,748 115,881 — 115,881 — Long-term borrowings (f) 74,906 72,219 — 72,219 — Junior subordinated debentures (g) 62,848 65,603 — 65,603 — Subordinated debentures (f) 49,601 52,870 — — 52,870 Fair Value Measurements at Reporting Date Using Carrying Value Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) December 31, 2018 Financial assets (Dollars in thousands) Securities held to maturity (a) U.S. Treasury securities $ 1,004 $ 1,015 $ — $ 1,015 $ — Agency mortgage-backed securities 252,484 250,928 — 250,928 — Agency collateralized mortgage obligations 332,775 326,724 — 326,724 — Single issuer trust preferred securities issued by banks 1,500 1,490 — 1,490 — Small business administration pooled securities 23,727 23,483 — 23,483 — Loans, net of allowance for loan losses (b) 6,812,792 6,635,209 — — 6,635,209 Federal Home Loan Bank stock (c) 15,683 15,683 — 15,683 — Cash surrender value of life insurance policies (d) 160,456 160,456 — 160,456 — Financial liabilities Deposit liabilities, other than time deposits (e) $ 6,716,017 $ 6,716,017 $ — $ 6,716,017 $ — Time certificates of deposits (f) 711,103 703,728 — 703,728 — Federal Home Loan Bank borrowings (f) 147,806 147,603 — 147,603 — Junior subordinated debentures (g) 76,173 73,827 — 73,827 — Subordinated debentures (f) 34,728 32,509 — — 32,509 (a) The fair values presented are based on quoted market prices, where available. If quoted market prices are not available, fair values are based on quoted market prices of comparable instruments and/or discounted cash flow analysis. (b) Fair value of loans is measured using the exit price valuation method, determined primarily by discounting the future cash flows using the current rates at which similar loans would be made to borrowers with similar credit ratings and for the same remaining maturities or cash flows, while incorporating liquidity and credit assumptions. Additionally, this amount excludes collateral dependent impaired loans, which are deemed to be marked to fair value on a nonrecurring basis. (c) FHLB stock has no quoted market value and is carried at cost, therefore the carrying amount approximates fair value. (d) Cash surrender value of life insurance is recorded at its cash surrender value (or the amount that can be realized upon surrender of the policy), therefore carrying amount approximates fair value. (e) Fair value of demand deposits, savings and interest checking accounts and money market deposits is the amount payable on demand at the reporting date. (f) Fair value was determined by discounting anticipated future cash payments using rates currently available for instruments with similar remaining maturities. (g) Fair value was determined based upon market prices of securities with similar terms and maturities.

REVENUE RECOGNITION (Tables)

REVENUE RECOGNITION (Tables)	12 Months Ended
	Dec. 31, 2019
Revenue Recognition [Abstract]
Disaggregation of Revenue [Table Text Block]	The following table presents the revenue streams that the Company has disaggregated for the periods indicated: Years Ended December 31 2019 2018 2017 (Dollars in thousands) Deposit account fees (inclusive of cash management fees) $ 20,040 $ 18,327 $ 17,822 Interchange fees 18,262 15,433 13,899 ATM fees 3,224 2,961 2,938 Investment management - wealth management and advisory services 25,940 23,441 21,644 Investment management - retail investments and insurance revenue 2,779 2,714 2,158 Merchant processing income 1,175 1,401 1,229 Other noninterest income 8,696 4,432 4,569 Total noninterest income in-scope of ASC 606 80,116 68,709 64,259 Total noninterest income out-of-scope of ASC 606 35,178 19,796 18,735 Total noninterest income $ 115,294 88,505 $ 82,994
Contract with Customer, Asset and Liability [Table Text Block]	The following table provides the amount of investment management revenue earned but not received as of the dates indicated: December 31, 2019 December 31, 2018 (Dollars in thousands) Receivables, included in other assets $ 2,341 $ 1,893

OTHER COMPREHENSIVE LOSS (Table

OTHER COMPREHENSIVE LOSS (Tables)	12 Months Ended
	Dec. 31, 2019
Equity [Abstract]
Schedule of Other Comprehensive Loss	The following table presents a reconciliation of the changes in the components of other comprehensive income (loss) for the periods indicated, including the amount of income tax (expense) benefit allocated to each component of other comprehensive income (loss): Year Ended December 31, 2019 Pre Tax Tax (Expense) After Tax (Dollars in thousands) Change in fair value of securities available for sale $ 12,055 $ (2,761 ) $ 9,294 Less: net security losses reclassified into other noninterest expense (1,462 ) 411 (1,051 ) Net change in fair value of securities available for sale 13,517 (3,172 ) 10,345 Change in fair value of cash flow hedges 16,725 (4,708 ) 12,017 Less: net cash flow hedge gains reclassified into interest income or interest expense 2,346 (660 ) 1,686 Net change in fair value of cash flow hedges 14,379 (4,048 ) 10,331 Net unamortized loss related to defined benefit pension and other postretirement adjustments arising during the period (2,123 ) 597 (1,526 ) Amortization of net actuarial gains (8 ) 2 (6 ) Amortization of net prior service costs 276 (78 ) 198 Net change in other comprehensive income for defined benefit postretirement plans (2) (1,855 ) 521 (1,334 ) Total other comprehensive income $ 26,041 $ (6,699 ) $ 19,342 Year Ended December 31, 2018 Pre Tax Tax (Expense) After Tax (Dollars in thousands) Change in fair value of securities available for sale $ (5,923 ) $ 1,422 $ (4,501 ) Less: net security gains reclassified into other noninterest income (expense) — — — Net change in fair value of securities available for sale (5,923 ) 1,422 (4,501 ) Change in fair value of cash flow hedges 7,717 (2,169 ) 5,548 Less: net cash flow hedge losses reclassified into interest income or interest expense (1) 1,000 (281 ) 719 Net change in fair value of cash flow hedges 6,717 (1,888 ) 4,829 Net unamortized gain related to defined benefit pension and other postretirement adjustments arising during the period 1,521 (428 ) 1,093 Amortization of net actuarial losses 372 (105 ) 267 Amortization of net prior service costs 276 (78 ) 198 Net change in other comprehensive income for defined benefit postretirement plans (2) 2,169 (611 ) 1,558 Total other comprehensive income $ 2,963 $ (1,077 ) $ 1,886 Year Ended December 31, 2017 Pre Tax Tax (Expense) After Tax (Dollars in thousands) Change in fair value of securities available for sale $ (996 ) $ 321 $ (675 ) Less: net security gains reclassified into other noninterest income (expense) 3 (1 ) 2 Net change in fair value of securities available for sale (999 ) 322 (677 ) Change in fair value of cash flow hedges 307 (125 ) 182 Less: net cash flow hedge losses reclassified into interest income or interest expense (1) (441 ) 180 (261 ) Net change in fair value of cash flow hedges 748 (305 ) 443 Net unamortized loss related to defined benefit pension and other postretirement adjustments arising during the period (995 ) 407 (588 ) Amortization of net actuarial losses 278 (113 ) 165 Amortization of net prior service costs 276 (113 ) 163 Net change in other comprehensive income for defined benefit postretirement plans (2) (441 ) 181 (260 ) Total other comprehensive loss $ (692 ) $ 198 $ (494 ) (1) Includes the amortization of the remaining balance of a realized but unrecognized gain, net of tax, from the termination of interest rate swaps in 2009. The original gain of $1.4 million , net of tax, was recognized in earnings through December 2018 , the original maturity date of the swap. The balance of the gain was amortized to $137,000 at December 31, 2017 . (2) The amortization of prior service costs is included in the computation of net periodic pension costs as disclosed in Note 15 - Employee Benefit Plans .
Schedule of Accumulated Other Comprehensive Income (Loss), Net of Tax	Information on the Company's accumulated other comprehensive income (loss), net of tax, is comprised of the following components for the periods indicated: Unrealized Gain (Loss) on Securities Unrealized Gain (Loss) on Cash Flow Hedge Deferred Gain on Hedge Transactions Defined Benefit Postretirement Plans Accumulated Other Comprehensive Income (Loss) (Dollars in Thousands) Beginning balance: January 1, 2017 $ 173 $ 361 $ 281 $ (2,152 ) $ (1,337 ) Other comprehensive income (loss) (677 ) 587 (144 ) (260 ) (494 ) Ending balance: December 31, 2017 $ (504 ) $ 948 $ 137 $ (2,412 ) $ (1,831 ) Opening balance reclassification (111 ) 205 29 (520 ) (397 ) Cumulative effect accounting adjustment (831 ) — — — (831 ) Other comprehensive income (loss) (4,501 ) 4,995 (166 ) 1,558 1,886 Ending balance: December 31, 2018 $ (5,947 ) $ 6,148 $ — $ (1,374 ) $ (1,173 ) Other comprehensive income (loss) 10,345 10,331 — (1,334 ) 19,342 Ending balance: December 31, 2019 $ 4,398 $ 16,479 $ — $ (2,708 ) $ 18,169

LEASES (Tables)

LEASES (Tables)	12 Months Ended
	Dec. 31, 2019
Leases [Abstract]
Lease, Cost [Table Text Block]	The following table provides information related to the Company's lease cost: For the year ended December 31, 2019 (Dollars in thousands) Operating lease cost $10,718 Short-term lease cost 116 Variable lease cost — Total lease cost $10,834
Lessee, Operating Lease, Liability, Maturity [Table Text Block]	The following table sets forth the undiscounted cash flows of base rent related to operating leases outstanding at December 31, 2019 with payments scheduled over the next five years and thereafter, including a reconciliation to the operating lease liability recognized in the Company's Consolidated Balance Sheet in other liabilities: (Dollars in thousands) 2020 $ 11,752 2021 11,052 2022 10,438 2023 8,528 2024 7,121 Thereafter 14,900 Total minimum lease payments 63,791 Less: amount representing interest 5,489 Present value of future minimum lease payments $ 58,302

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Tables)	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Schedule of Off-Balance Sheet Financial Instruments	The following table summarizes the above financial instruments at the dates indicated: As of December 31 2019 2018 (Dollars in thousands) Commitments to extend credit $ 3,337,930 $ 2,639,689 Standby letters of credit $ 21,565 $ 16,708 Deferred standby letter of credit fees $ 158 $ 122 Loans sold with recourse $ 404,532 $ —

REGULATORY CAPITAL REQUIREMEN_2

REGULATORY CAPITAL REQUIREMENTS (Tables)	12 Months Ended
	Dec. 31, 2019
Banking and Thrift [Abstract]
Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations	The Company’s and the Bank’s actual capital amounts and ratios as of December 31, 2019 and 2018 are also presented in the table that follows: Actual For Capital To Be Well Capitalized Amount Ratio Amount Ratio Amount Ratio December 31, 2019 (Dollars in thousands) Independent Bank Corp. Total capital (to risk weighted assets) $ 1,352,341 14.83 % $ 729,291 ≥ 8.0 % N/A N/A Common equity tier 1 capital (to risk weighted assets) $ 1,171,963 12.86 % $ 410,226 ≥ 4.5 % N/A N/A Tier 1 capital (to risk weighted assets) $ 1,232,963 13.53 % $ 546,969 ≥ 6.0 % N/A N/A Tier 1 capital (to average assets) leverage $ 1,232,963 11.28 % $ 437,271 ≥ 4.0 % N/A N/A Rockland Trust Company Total capital (to risk weighted assets) $ 1,275,611 14.00 % $ 728,868 ≥ 8.0 % $ 911,085 ≥ 10.0 % Common equity tier 1 capital (to risk weighted assets) $ 1,205,740 13.23 % $ 409,988 ≥ 4.5 % $ 592,205 ≥ 6.5 % Tier 1 capital (to risk weighted assets) $ 1,205,740 13.23 % $ 546,651 ≥ 6.0 % $ 728,868 ≥ 8.0 % Tier 1 capital (to average assets) leverage $ 1,205,740 11.06 % $ 435,886 ≥ 4.0 % $ 544,857 ≥ 5.0 % December 31, 2018 (Dollars in thousands) Independent Bank Corp. Total capital (to risk weighted assets) $ 992,454 14.45 % $ 549,297 ≥ 8.0 % N/A N/A Common equity tier 1 capital (to risk weighted assets) $ 818,176 11.92 % $ 308,980 ≥ 4.5 % N/A N/A Tier 1 capital (to risk weighted assets) $ 892,176 12.99 % $ 411,973 ≥ 6.0 % N/A N/A Tier 1 capital (to average assets) $ 892,176 10.69 % $ 333,754 ≥ 4.0 % N/A N/A Rockland Trust Company Total capital (to risk weighted assets) $ 937,574 13.66 % $ 549,036 ≥ 8.0 % $ 686,295 ≥ 10.0 % Common equity tier 1 capital (to risk weighted assets) $ 872,024 12.71 % $ 308,833 ≥ 4.5 % $ 446,092 ≥ 6.5 % Tier 1 capital (to risk weighted assets) $ 872,024 12.71 % $ 411,777 ≥ 6.0 % $ 549,036 ≥ 8.0 % Tier 1 capital (to average assets) $ 872,024 10.46 % $ 333,595 ≥ 4.0 % $ 416,994 ≥ 5.0 %

PARENT COMPANY FINANCIALS ONLY

PARENT COMPANY FINANCIALS ONLY (Tables)	12 Months Ended
	Dec. 31, 2019
Condensed Financial Information Disclosure [Abstract]
Schedule of Condensed Balance Sheets	BALANCE SHEETS December 31 2019 2018 (Dollars in thousands) Assets Cash (1) $ 135,688 $ 64,256 Investments in subsidiaries (2) 1,743,435 1,128,407 Prepaid income taxes 31,586 1,014 Deferred tax asset 612 — Derivative instruments (1) 290 1,711 Other assets — 37 Total assets $ 1,911,611 $ 1,195,425 Liabilities and stockholders’ equity Dividends payable $ 15,126 $ 10,671 Long-term borrowings (less unamortized debt issuance costs of $94) 74,906 — Junior subordinated debentures (less unamortized debt issuance costs of $40 and $118) 62,848 76,173 Subordinated debentures (less unamortized debt issuance costs of $399 and $272) 49,601 34,728 Other liabilities 987 363 Total liabilities 203,468 121,935 Stockholders’ equity 1,708,143 1,073,490 Total liabilities and stockholders’ equity $ 1,911,611 $ 1,195,425 (1) Entire balance eliminates in consolidation. (2)
Schedule of Condensed Statements of Income	STATEMENTS OF INCOME Years Ended December 31 2019 2018 2017 (Dollars in thousands) Income Dividends received from subsidiaries (1) $ 181,790 $ 71,255 $ 47,006 Interest income (2) — — 50 Total income 181,790 71,255 47,056 Expenses Interest expense 8,236 4,234 3,995 Total expenses 8,236 4,234 3,995 Income before income taxes and equity in undistributed income of subsidiaries 173,554 67,021 43,061 Income tax benefit (2,262 ) (1,151 ) (1,523 ) Income of parent company 175,816 68,172 44,584 Equity (deficit) in undistributed income of subsidiaries (10,641 ) 53,450 42,620 Net income $ 165,175 $ 121,622 $ 87,204 (1) Majority of balance eliminates in consolidation. (2) Entire balance eliminated in consolidation.
Schedule of Condensed Statements of Cash Flows	STATEMENTS OF CASH FLOWS Years Ended December 31 2019 2018 2017 (Dollars in thousands) Cash flows from operating activities Net income $ 165,175 $ 121,622 $ 87,204 Adjustments to reconcile net income to cash provided by operating activities Amortization 157 54 12 Deferred income tax expense 1,021 49 51 Change in prepaid income taxes and other assets 20,556 135 (99 ) Change in other liabilities (4,613 ) 6 (562 ) Deficit (equity) in undistributed income of subsidiaries 10,641 (53,450 ) (42,620 ) Net cash provided by operating activities 192,937 68,416 43,986 Cash flows provided by (used in) investing activities Cash paid for acquisitions, net of cash acquired (1) (148,297 ) (13,649 ) (4,834 ) Net cash used in investing activities (148,297 ) (13,649 ) (4,834 ) Cash flows used in financing activities Proceeds from line of credit, net of issuance costs 49,980 — — Repayment of line of credit, net of issuance costs (49,980 ) — — Proceeds from long-term debt, net of issuance costs 74,867 — — Repayments of junior subordinated debentures, net of issuance costs (13,329 ) — — Proceeds from issuance of subordinated debentures, net of issuance costs 49,526 — — Repayments of subordinated debentures, net of issuance costs (34,767 ) — — Restricted stock awards issued, net of awards surrendered (1,463 ) (1,371 ) (1,422 ) Net proceeds from exercise of stock options 281 184 214 Proceeds from shares issued under the direct stock purchase plan 4,951 2,712 1,636 Common dividends paid (53,274 ) (40,167 ) (34,045 ) Net cash provided by (used in) financing activities 26,792 (38,642 ) (33,617 ) Net increase in cash and cash equivalents 71,432 16,125 5,535 Cash and cash equivalents at the beginning of the year 64,256 48,131 42,596 Cash and cash equivalents at the end of the year $ 135,688 $ 64,256 $ 48,131 (1) The majority of the net assets acquired at the parent company represented each of the acquired companies' investments in their wholly owned subsidiaries, which were eliminated in consolidation at December 31, 2019 , 2018 , and 2017 , respectively.

SELECTED QUARTERLY FINANCIAL _2

SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) (Tables)	12 Months Ended
	Dec. 31, 2019
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Information	First Quarter Second Quarter Third Quarter Fourth Quarter 2019 2018 2019 2018 2019 2018 2019 2018 (Dollars in thousands, except per share data) Interest income $ 91,543 $ 73,749 $ 122,144 $ 79,167 $ 119,624 $ 82,875 $ 113,703 $ 87,910 Interest expense 9,018 5,278 16,125 5,999 15,026 6,641 13,710 7,618 Net interest income 82,525 68,471 106,019 73,168 104,598 76,234 99,993 80,292 Provision for loan losses 1,000 500 1,000 2,000 — 1,075 4,000 1,200 Total noninterest income 21,533 19,863 28,648 21,887 31,816 23,264 33,297 23,491 Total noninterest expenses 56,311 53,451 93,032 52,688 67,533 55,439 67,445 64,391 Provision for income taxes 11,522 6,828 10,007 9,249 17,036 9,969 14,368 8,258 Net income $ 35,225 $ 27,555 $ 30,628 $ 31,118 $ 51,845 $ 33,015 $ 47,477 $ 29,934 Basic earnings per share $ 1.25 $ 1.00 $ 0.89 $ 1.13 $ 1.51 $ 1.20 $ 1.38 $ 1.08 Diluted earnings per share $ 1.25 $ 1.00 $ 0.89 $ 1.13 $ 1.51 $ 1.20 $ 1.38 $ 1.07 Weighted average common shares (basic) 28,106,184 27,486,573 34,313,492 27,526,653 34,361,176 27,537,841 34,374,953 27,815,437 Common stock equivalents 54,466 67,381 41,878 54,525 39,390 63,499 46,245 58,576 Weighted average common shares (diluted) 28,160,650 27,553,954 34,355,370 27,581,178 34,400,566 27,601,340 34,421,198 27,874,013 Unusual or infrequently occurring items Items within noninterest income Gain on sale of loans $ — $ — $ — $ — $ 951 $ — $ — $ — Total $ — $ — $ — $ — $ 951 $ — $ — $ — Items within noninterest expense Merger and acquisition expense $ 1,032 $ — $ 24,696 $ 434 $ 705 $ 2,688 $ — $ 8,046 Adjustment for tax effect of previously incurred merger and acquisition expense 650 — — — — — — — Items within provision for income taxes Total $ 1,682 $ — $ 24,696 $ 434 $ 705 $ 2,688 $ — $ 8,046

TRANSACTIONS WITH RELATED PAR_2

TRANSACTIONS WITH RELATED PARTIES Activity of Loans to Related Parties (Tables)	12 Months Ended
	Dec. 31, 2019
Related Party Transaction [Line Items]
Schedule of Related Party Transactions [Table Text Block]	The following information represents annual activity of loans to related parties for the periods indicated: 2019 2018 (Dollars in thousands) Principal balance of loans outstanding at beginning of year $ 41,170 $ 52,458 Loan advances (1) 49,771 14,862 Loan payments/payoffs (35,111 ) (14,057 ) Reduction for retired directors — (12,093 ) Principal balance of loans outstanding at end of year $ 55,830 $ 41,170 (1) The 2019 amount includes $7.0 million of BHB acquired loans associated with a director during the year, which represent the outstanding loan balances at the effective date of appointment.

SUMMARY OF SIGNIFICANT ACCOUN_4

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)	12 Months Ended
	Dec. 31, 2019
Core Deposits [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life	10 years
Noncompete Agreements [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life	1 year
Noncompete Agreements [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life	3 years
Customer Lists [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life	12 years
Lease Agreements [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life	3 years
Lease Agreements [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life	30 years

SUMMARY OF SIGNIFICANT ACCOUN_5

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details Textual) $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)centerbranch	Dec. 31, 2018USD ($)
Accounting Policies [Line Items]
Reserve for unfunded loan commitments | $	$ 2.1	$ 1.3
Maximum [Member]
Accounting Policies [Line Items]
Lease Option Period	15 years
Loans Receivable [Member] | Lender Concentration Risk [Member] | Residential Building [Member]
Accounting Policies [Line Items]
Loans of nonresidential buildings to total loan portfolio	17.50%	15.07%
Full Service Retail Branch [Member] | Bank [Member]
Accounting Policies [Line Items]
Number of branches | branch	95
Limited Service Retail Branch [Member] | Bank [Member]
Accounting Policies [Line Items]
Number of branches | branch	2
Commercial Banking Center [Member] | Bank [Member]
Accounting Policies [Line Items]
Number of centers	15
Investment Management Office [Member] | Bank [Member]
Accounting Policies [Line Items]
Number of centers	9
Mortgage Lending Center [Member] | Bank [Member]
Accounting Policies [Line Items]
Number of centers	7

ACQUISITIONS (Details)

ACQUISITIONS (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Apr. 01, 2019	Dec. 31, 2018	Nov. 16, 2018	Dec. 31, 2017
Assets
Goodwill	$ 506,206		$ 256,105		$ 231,806
Blue Hills Bancorp, Inc. [Member]
Assets
Cash		$ 56,331
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Investments		196,937
Loans		2,073,714
Premises and equipment		24,253
Goodwill		250,101
Core deposit intangible		19,870
Other assets		146,192
Total assets acquired		2,767,398
Liabilities
Deposits		1,930,436
Borrowings		124,817
Other liabilities		50,857
Total liabilities assumed		2,106,110
Purchase price		$ 661,288
MNB Bancorp [Member]
Assets
Cash				$ 6,743
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Investments				25,358
Loans				293,498
Premises and equipment				1,904
Goodwill				24,299
Core deposit intangible				8,588
Other assets				8,639
Total assets acquired				369,029
Liabilities
Deposits				278,204
Borrowings				33,093
Other liabilities				1,609
Total liabilities assumed				312,906
Purchase price				$ 56,123

ACQUISITIONS (Details 2)

ACQUISITIONS (Details 2) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Blue Hills Bancorp, Inc. [Member]
Business Acquisition [Line Items]
Net interest income after provision for loan losses	$ 408,918	$ 371,264
Net income	$ 129,385	146,178
MNB Bancorp [Member]
Business Acquisition [Line Items]
Net interest income after provision for loan losses		304,049	$ 267,104
Net income		$ 122,310	$ 88,518

ACQUISITIONS PCI Loans Acquired

ACQUISITIONS PCI Loans Acquired (Details) - Blue Hills Bancorp, Inc. [Member] $ in Thousands	Apr. 01, 2019USD ($)
Business Acquisition [Line Items]
Contractually required principal and interest at acquisition	$ 14,849
Contractual cash flows not expected to be collected	(5,717)
Expected cash flows at acquisition	9,132
Interest component of expected cash flows	(1,464)
Basis in PCI loans at acquisition - estimated fair value	$ 7,668

ACQUISITIONS (Details Textual)

ACQUISITIONS (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	Apr. 01, 2019	Nov. 16, 2018	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Acquisition Related Costs			$ 0	$ 705	$ 24,696	$ 1,032	$ 8,046	$ 2,688	$ 434	$ 0	$ 26,433	$ 11,168	$ 3,393
Business Combination, Pro Forma Information [Abstract]
Business Combination, Acquired Receivable, Fair Value	$ 23,200
Blue Hills Bancorp, Inc. [Member]
Business Acquisition [Line Items]
Equity Interest Issued or Issuable Shareholders Option To Receive, Cash Per Share	$ 5.25
Number of shares of company stock issued for each share of Central common stock (in shares)	0.2308
Business transaction value	$ 661,300
Cost of acquired entity, cash paid	$ 161,600
Increase in acquirer outstanding shares	6,166,010
Acquisition Related Costs											26,000
Loans acquired	$ 2,073,714
Combination of INDB and Blue Hills Bancorp, Inc. [Member]
Business Acquisition [Line Items]
Acquisition Related Costs											$ 57,300
MNB Bancorp [Member]
Business Acquisition [Line Items]
Equity Interest Issued or Issuable Shareholders Option To Receive, Cash Per Share		$ 275
Number of shares of company stock issued for each share of Central common stock (in shares)		3.55
Value of shares of company stock issued for each share of acquiree stock (in dollars per share)		$ 285.38
Company's closing price per share (in dollars per share)		$ 80.39
Business transaction value		$ 56,100
Cost of acquired entity, percentage cash		25.00%
Business Acquisition, Cost of Acquired Entity, Percentage Stock Consideration		75.00%
Cost of acquired entity, cash paid		$ 13,600
Consideration Transferred, Equity Interests Issued and Issuable		$ 42,500
Increase in acquirer outstanding shares		528,353
Acquisition Related Costs			$ 8,800
Loans acquired		$ 293,498
Combination of INDB and MNB Bancorp [Member]
Business Acquisition [Line Items]
Acquisition Related Costs												$ 7,500

SECURITIES Equity Securities Ga

SECURITIES Equity Securities Gain Loss (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Equity Securities, FV-NI, Gain (Loss) [Abstract]	$ 1,566	$ (1,225)
Equity Securities, FV-NI, Realized Gain (Loss)	18	874
Equity Securities, FV-NI, Unrealized Gain (Loss)	$ 1,548	$ (2,099)

Available for Sale and Held to

Available for Sale and Held to Maturity securities (Details 1) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Debt Securities, Available-for-sale and Held-to-maturity	$ 1,179,687	$ 1,046,392
Reconciliation of fair value of securities:
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	6,118	1,233
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(397)	(9,029)
Equity Securities, FV-NI	426,424	442,752
Debt Securities, Available-for-sale, Amortized Cost	420,703	450,548
Amortized Cost	740,806	611,490
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	13,428	2,533
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(971)	(10,383)
Fair Value	753,263	603,640
Available for Sale Securities and Held to Maturity Securities Amortized Cost	1,161,509	1,062,038
Available for Sale Securities and Held to Maturity Securities Gross Unrealized Gains	19,546	3,766
Available for Sale Securities and Held to Maturity Securities Gross Unrealized Losses	(1,368)	(19,412)
U.S. government agency securities
Reconciliation of fair value of securities:
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	642
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	(439)
Equity Securities, FV-NI	33,115	32,038
Debt Securities, Available-for-sale, Amortized Cost	32,473	32,477
Amortized Cost	12,874	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	123
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	0
Fair Value	12,997
U.S. treasury securities [Member]
Reconciliation of fair value of securities:
Amortized Cost	4,032	1,004
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	21	11
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	0
Fair Value	4,053	1,015
Agency mortgage-backed securities [Member]
Reconciliation of fair value of securities:
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	3,456	1,020
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(4)	(3,406)
Equity Securities, FV-NI	247,000	220,105
Debt Securities, Available-for-sale, Amortized Cost	243,548	222,491
Amortized Cost	397,414	252,484
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	8,445	1,548
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(57)	(3,104)
Fair Value	405,802	250,928
Agency collateralized mortgage obligations [Member]
Reconciliation of fair value of securities:
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1,225	197
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(19)	(3,435)
Equity Securities, FV-NI	88,511	134,911
Debt Securities, Available-for-sale, Amortized Cost	87,305	138,149
Amortized Cost	293,662	332,775
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	4,501	869
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(849)	(6,920)
Fair Value	297,314	326,724
State, county, and municipal securities [Member]
Reconciliation of fair value of securities:
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	19	16
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Equity Securities, FV-NI	1,396	1,735
Debt Securities, Available-for-sale, Amortized Cost	1,377	1,719
Single issuer trust preferred securities issued by banks [Member]
Reconciliation of fair value of securities:
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	5
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	(10)
Equity Securities, FV-NI	493	707
Debt Securities, Available-for-sale, Amortized Cost	488	717
Amortized Cost	1,500	1,500
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(10)	(10)
Fair Value	1,490	1,490
Pooled trust preferred securities issued by banks and insurers
Reconciliation of fair value of securities:
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(374)	(349)
Equity Securities, FV-NI	1,114	1,329
Debt Securities, Available-for-sale, Amortized Cost	1,488	1,678
Small Business Administration Pooled Securities [Member]
Reconciliation of fair value of securities:
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	771	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	(1,390)
Equity Securities, FV-NI	54,795	51,927
Debt Securities, Available-for-sale, Amortized Cost	54,024	53,317
Amortized Cost	31,324	23,727
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	338	105
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(55)	(349)
Fair Value	$ 31,607	$ 23,483

Contractural maturities (Detail

Contractural maturities (Details 3) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	$ 420,703	$ 450,548
Available for Sale, Fair Value
Debt Securities, Available-for-sale	426,424	442,752
Held to Maturity, Amortized Cost
Amortized Cost	740,806	611,490
Held to Maturity, Fair Value
Fair Value	753,263	603,640
AvailableForSaleandHeldToMaturityDebtSecuritiesMaturitiesWithinOneYearAmortizedCost	14,962
AvailableForSaleandHeldToMaturityDebtSecuritiesMaturitiesWithinOneYearFairValue	14,992
AvailableForSaleandHeldToMaturityDebtSecuritiesMaturitiesAfterOneThroughFiveYearsAmortizedCost	104,891
AvailableForSaleandHeldToMaturityDebtSecuritiesMaturitiesAfterOneThroughFiveYearsFair Value	105,531
AvailableForSaleandHeldToMaturityDebtSecuritiesMaturitiesAfterFiveThroughTenYearsAmortizedCost	104,614
AvailableForSaleandHeldToMaturityDebtSecuritiesMaturitiesAfterFiveThroughTenYearsFairValue	106,983
AvailableForSaleandHeldToMaturityDebtSecuritiesMaturitiesAfterTenYearsAmortizedCost	937,042
AvailableForSaleandHeldToMaturityDebtSecuritiesMaturitiesAfterTenYearsFairValue	952,181
AvailableForSaleandHeldToMaturityDebtSecuritiesAmortizedCost	1,161,509
Debt Securities, Available-for-sale and Held-to-maturity Fair Value	1,179,687	1,046,392
U.S. government agency securities
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Due in one year or less	10,000
Due after one year to five years	10,002
Due after five to ten years	12,471
Due after ten years	0
Debt Securities, Available-for-sale, Amortized Cost	32,473	32,477
Available for Sale, Fair Value
Due in one year or less	10,003
Due in one year or less	10,154
Due after five to ten years	12,958
Due after ten years	0
Debt Securities, Available-for-sale	33,115	32,038
Held to Maturity, Amortized Cost
Due in one year or less	4,962
Due after one year to five years	7,912
Due after five to ten years	0
Due after ten years	0
Amortized Cost	12,874	0
Held to Maturity, Fair Value
Due in one year or less	4,989
Due after one year to five years	8,008
Due after five to ten years	0
Due after ten years	0
Fair Value	12,997
Debt Securities [Member]
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Due in one year or less	10,000
Due after one year to five years	82,135
Due after five to ten years	67,458
Due after ten years	261,110
Available for Sale, Fair Value
Due in one year or less	10,003
Due in one year or less	82,652
Due after five to ten years	69,342
Due after ten years	264,427
Available-for-sale Securities	426,424
Held to Maturity, Amortized Cost
Due in one year or less	4,962
Due after one year to five years	22,756
Due after five to ten years	37,156
Due after ten years	675,932
Held to Maturity, Fair Value
Due in one year or less	4,989
Due after one year to five years	22,879
Due after five to ten years	37,641
Due after ten years	687,754
Fair Value	753,263
US Treasury Securities [Member]
Held to Maturity, Amortized Cost
Due in one year or less	0
Due after one year to five years	4,032
Due after five to ten years	0
Due after ten years	0
Amortized Cost	4,032	1,004
Held to Maturity, Fair Value
Due in one year or less	0
Due after one year to five years	4,053
Due after five to ten years	0
Due after ten years	0
Fair Value	4,053	1,015
Agency mortgage-backed securities
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Due in one year or less	0
Due after one year to five years	70,945
Due after five to ten years	54,798
Due after ten years	117,805
Debt Securities, Available-for-sale, Amortized Cost	243,548	222,491
Available for Sale, Fair Value
Due in one year or less	0
Due in one year or less	71,305
Due after five to ten years	56,181
Due after ten years	119,514
Debt Securities, Available-for-sale	247,000	220,105
Held to Maturity, Amortized Cost
Due in one year or less	0
Due after one year to five years	10,812
Due after five to ten years	35,656
Due after ten years	350,946
Amortized Cost	397,414	252,484
Held to Maturity, Fair Value
Due in one year or less	0
Due after one year to five years	10,818
Due after five to ten years	36,151
Due after ten years	358,833
Fair Value	405,802	250,928
Agency collateralized mortgage obligations [Member]
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Due in one year or less	0
Due after one year to five years	0
Due after five to ten years	0
Due after ten years	87,305
Debt Securities, Available-for-sale, Amortized Cost	87,305	138,149
Available for Sale, Fair Value
Due in one year or less	0
Due in one year or less	0
Due after five to ten years	0
Due after ten years	88,511
Debt Securities, Available-for-sale	88,511	134,911
Held to Maturity, Amortized Cost
Due in one year or less	0
Due after one year to five years	0
Due after five to ten years	0
Due after ten years	293,662
Amortized Cost	293,662	332,775
Held to Maturity, Fair Value
Due in one year or less	0
Due after one year to five years	0
Due after five to ten years	0
Due after ten years	297,314
Fair Value	297,314	326,724
US States and Political Subdivisions Debt Securities [Member]
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Due in one year or less	0
Due after one year to five years	1,188
Due after five to ten years	189
Due after ten years	0
Debt Securities, Available-for-sale, Amortized Cost	1,377	1,719
Available for Sale, Fair Value
Due in one year or less	0
Due in one year or less	1,193
Due after five to ten years	203
Due after ten years	0
Debt Securities, Available-for-sale	1,396	1,735
Single issuer trust preferred securities issued by banks [Member]
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Due in one year or less	0
Due after one year to five years	0
Due after five to ten years	0
Due after ten years	488
Debt Securities, Available-for-sale, Amortized Cost	488	717
Available for Sale, Fair Value
Due in one year or less	0
Due in one year or less	0
Due after five to ten years	0
Due after ten years	493
Debt Securities, Available-for-sale	493	707
Held to Maturity, Amortized Cost
Due in one year or less	0
Due after one year to five years	0
Due after five to ten years	1,500
Due after ten years	0
Amortized Cost	1,500	1,500
Held to Maturity, Fair Value
Due in one year or less	0
Due after one year to five years	0
Due after five to ten years	1,490
Due after ten years	0
Fair Value	1,490	1,490
Pooled Trust Preferred Securities Issued By Banks And Insurers [Member]
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Due in one year or less	0
Due after one year to five years	0
Due after five to ten years	0
Due after ten years	1,488
Debt Securities, Available-for-sale, Amortized Cost	1,488	1,678
Available for Sale, Fair Value
Due in one year or less	0
Due in one year or less	0
Due after five to ten years	0
Due after ten years	1,114
Debt Securities, Available-for-sale	1,114	1,329
Small Business Administration Pooled Securities [Member]
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Due in one year or less	0
Due after one year to five years	0
Due after five to ten years	0
Due after ten years	54,024
Debt Securities, Available-for-sale, Amortized Cost	54,024	53,317
Available for Sale, Fair Value
Due in one year or less	0
Due in one year or less	0
Due after five to ten years	0
Due after ten years	54,795
Debt Securities, Available-for-sale	54,795	51,927
Held to Maturity, Amortized Cost
Due in one year or less	0
Due after one year to five years	0
Due after five to ten years	0
Due after ten years	31,324
Amortized Cost	31,324	23,727
Held to Maturity, Fair Value
Due in one year or less	0
Due after one year to five years	0
Due after five to ten years	0
Due after ten years	31,607
Fair Value	$ 31,607	$ 23,483

Unrealized Losses (Details 4)

Unrealized Losses (Details 4) $ in Thousands	Dec. 31, 2019USD ($)holding	Dec. 31, 2018USD ($)holding
Summary of gross unrealized losses and fair value of investments
No of holdings | holding	32	205
Fair value, less than 12 months	$ 89,834	$ 202,901
Fair value, 12 months or longer	40,229	566,107
Fair value, Total	130,063	769,008
Unrealized losses, Total	(1,368)	(19,412)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months	(329)	(2,486)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months	(1,039)	$ (16,926)
U.S. government agency securities
Gain (Loss) on Securities [Line Items]
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost	10,000
Summary of gross unrealized losses and fair value of investments
No of holdings | holding		3
Fair value, less than 12 months		$ 9,960
Fair value, 12 months or longer		22,078
Fair value, Total		32,038
Unrealized losses, Total		(439)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months		(43)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months		$ (396)
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value	10,003
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	10,002
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	12,471
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	12,958
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	0
Agency mortgage-backed securities [Member]
Gain (Loss) on Securities [Line Items]
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost	$ 0
Summary of gross unrealized losses and fair value of investments
No of holdings | holding	12	144
Fair value, less than 12 months	$ 34,009	$ 104,616
Fair value, 12 months or longer	243	222,850
Fair value, Total	34,252	327,466
Unrealized losses, Total	(61)	(6,510)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months	(59)	(1,363)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months	(2)	$ (5,147)
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	70,945
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	54,798
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	56,181
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	117,805
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	119,514
Single issuer trust preferred securities issued by banks [Member]
Gain (Loss) on Securities [Line Items]
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost	0
Summary of gross unrealized losses and fair value of investments
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	0
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	488
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	493
Agency collateralized mortgage obligations [Member]
Gain (Loss) on Securities [Line Items]
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost	$ 0
Summary of gross unrealized losses and fair value of investments
No of holdings | holding	17	48
Fair value, less than 12 months	$ 48,476	$ 57,871
Fair value, 12 months or longer	37,382	279,229
Fair value, Total	85,858	337,100
Unrealized losses, Total	(868)	(10,355)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months	(215)	(398)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months	(653)	$ (9,957)
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	0
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	87,305
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	88,511
US States and Political Subdivisions Debt Securities [Member]
Gain (Loss) on Securities [Line Items]
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost	0
Summary of gross unrealized losses and fair value of investments
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	1,188
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	189
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	203
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	$ 0
Single issuer trust preferred securities issued by banks and insurers
Summary of gross unrealized losses and fair value of investments
No of holdings | holding	1	2
Fair value, less than 12 months	$ 0	$ 2,197
Fair value, 12 months or longer	1,490	0
Fair value, Total	1,490	2,197
Unrealized losses, Total	(10)	(20)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months	0	(20)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months	(10)	$ 0
Pooled trust preferred securities issued by banks and insurers
Gain (Loss) on Securities [Line Items]
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost	$ 0
Summary of gross unrealized losses and fair value of investments
No of holdings | holding	1	1
Fair value, less than 12 months	$ 0	$ 0
Fair value, 12 months or longer	1,114	1,329
Fair value, Total	1,114	1,329
Unrealized losses, Total	(374)	(349)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months	0	0
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months	(374)	$ (349)
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	0
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	1,488
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	1,114
Small Business Administration Pooled Securities [Member]
Gain (Loss) on Securities [Line Items]
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost	$ 0
Summary of gross unrealized losses and fair value of investments
No of holdings | holding	1	7
Fair value, less than 12 months	$ 7,349	$ 28,257
Fair value, 12 months or longer	0	40,621
Fair value, Total	7,349	68,878
Unrealized losses, Total	(55)	(1,739)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months	(55)	(662)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months	0	$ (1,077)
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	0
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	54,024
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	$ 54,795

SECURITIES (Details Textual)

SECURITIES (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Securities, Trading	$ 2,200	$ 1,500
Equity Securities, FV-NI	21,261	19,477
Investments in obligations of individual states, counties or municipalities which exceed 10% of equity	0	0
Debt Securities, Available-for-sale	426,424	442,752
Callable securities in investment portfolio	17,400
Investment securities pledged	375,500	361,100
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Period Increase (Decrease)	0	0	$ 0
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Credit Losses on Debt Securities Held	$ 0	$ 0

Allowance Allocations (Details)

Allowance Allocations (Details)	3 Months Ended								12 Months Ended
	Dec. 31, 2019USD ($)	Sep. 30, 2019USD ($)	Jun. 30, 2019USD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2019USD ($)contract	Dec. 31, 2018USD ($)contract	Dec. 31, 2017USD ($)contract
Financing Receivable Impaired [Line Items]
Unamortized Loan Commitment and Origination fees	$ 7,100,000				$ 7,089,000				$ 7,100,000	$ 7,089,000	$ 6,100,000
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance				$ 64,293,000				$ 60,643,000	64,293,000	60,643,000	61,566,000
Charge-offs									(5,205,000)	(2,597,000)	(6,209,000)
Recoveries									2,652,000	1,472,000	2,336,000
Provision (benefit)	4,000,000	$ 0	$ 1,000,000	1,000,000	1,200,000	$ 1,075,000	$ 2,000,000	500,000	6,000,000	4,775,000	2,950,000
Ending balance	67,740,000				64,293,000				67,740,000	64,293,000	60,643,000
Ending balance: collectively evaluated for impairment	66,760,000				63,214,000				66,760,000	63,214,000	59,301,000
Ending balance: individually evaluated for impairment	980,000				1,079,000				980,000	1,079,000	1,342,000
Financing receivables ending balance:
Financing Receivable, Collectively Evaluated for Impairment	8,809,155,000				6,838,339,000				8,809,155,000	6,838,339,000	6,269,729,000
Individually evaluated for impairment	49,628,000				59,060,000				49,628,000	59,060,000	72,801,000
Financing Receivable, after Allowance for Credit Loss	6,119,185,000				4,874,718,000				6,119,185,000	4,874,718,000
Total loans	8,873,639,000				6,906,194,000				$ 8,873,639,000	$ 6,906,194,000	$ 6,355,553,000	[1]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | contract									0	0	1
Commercial and Industrial [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance				15,760,000				13,256,000	$ 15,760,000	$ 13,256,000	$ 16,921,000
Charge-offs									(244,000)	(355,000)	(3,891,000)
Recoveries									1,131,000	182,000	615,000
Provision (benefit)									947,000	2,677,000	(389,000)
Ending balance	17,594,000				15,760,000				17,594,000	15,760,000	13,256,000
Ending balance: collectively evaluated for impairment	17,468,000				15,753,000				17,468,000	15,753,000	13,246,000
Ending balance: individually evaluated for impairment	126,000				7,000				126,000	7,000	10,000
Financing receivables ending balance:
Financing Receivable, Collectively Evaluated for Impairment	1,370,580,000				1,064,800,000				1,370,580,000	1,064,800,000	853,885,000
Individually evaluated for impairment	24,456,000				28,829,000				24,456,000	28,829,000	34,643,000
Financing Receivable, after Allowance for Credit Loss	1,395,036,000				1,093,629,000				1,395,036,000	1,093,629,000
Total loans	1,395,036,000				1,093,629,000				1,395,036,000	1,093,629,000	$ 888,528,000
Financing Receivable, before Allowance for Credit Loss	1,395,036,000				1,093,629,000				1,395,036,000	1,093,629,000
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts											122,000
Commercial Real Estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance				32,370,000				31,453,000	32,370,000	31,453,000	$ 30,369,000
Charge-offs									(2,614,000)	(82,000)	(39,000)
Recoveries									152,000	188,000	385,000
Provision (benefit)									3,027,000	811,000	738,000
Ending balance	32,935,000				32,370,000				32,935,000	32,370,000	31,453,000
Ending balance: collectively evaluated for impairment	32,887,000				32,333,000				32,887,000	32,333,000	31,411,000
Ending balance: individually evaluated for impairment	48,000				37,000				48,000	37,000	42,000
Financing receivables ending balance:
Financing Receivable, Collectively Evaluated for Impairment	3,987,848,000				3,235,418,000				3,987,848,000	3,235,418,000	3,093,945,000
Individually evaluated for impairment	8,337,000				10,839,000				8,337,000	10,839,000	16,638,000
Financing Receivable, after Allowance for Credit Loss	4,002,359,000				3,251,248,000				4,002,359,000	3,251,248,000
Total loans	4,002,359,000				3,251,248,000				4,002,359,000	3,251,248,000	3,116,561,000
Financing Receivable, before Allowance for Credit Loss	4,002,359,000				3,251,248,000				4,002,359,000	3,251,248,000
Construction Loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance				5,158,000				5,698,000	5,158,000	5,698,000	4,522,000
Charge-offs									0	0	0
Recoveries									0	0	0
Provision (benefit)									895,000	(540,000)	1,176,000
Ending balance	6,053,000				5,158,000				6,053,000	5,158,000	5,698,000
Ending balance: collectively evaluated for impairment	6,053,000				5,158,000				6,053,000	5,158,000	5,698,000
Ending balance: individually evaluated for impairment	0				0				0	0
Financing receivables ending balance:
Financing Receivable, Collectively Evaluated for Impairment	547,293,000				365,165,000				547,293,000	365,165,000	401,797,000
Individually evaluated for impairment	0				0				0	0	0
Financing Receivable, after Allowance for Credit Loss	547,293,000				365,165,000				547,293,000	365,165,000
Total loans	547,293,000				365,165,000				547,293,000	365,165,000	401,797,000
Financing Receivable, before Allowance for Credit Loss	547,293,000				365,165,000				547,293,000	365,165,000
Small Business [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance				1,756,000				1,577,000	1,756,000	1,577,000	1,502,000
Charge-offs									(509,000)	(372,000)	(302,000)
Recoveries									122,000	46,000	114,000
Provision (benefit)									377,000	505,000	263,000
Ending balance	1,746,000				1,756,000				1,746,000	1,756,000	1,577,000
Ending balance: collectively evaluated for impairment	1,738,000				1,755,000				1,738,000	1,755,000	1,576,000
Ending balance: individually evaluated for impairment	8,000				1,000				8,000	1,000	1,000
Financing receivables ending balance:
Financing Receivable, Collectively Evaluated for Impairment	173,960,000				164,135,000				173,960,000	164,135,000	131,667,000
Individually evaluated for impairment	537,000				541,000				537,000	541,000	703,000
Financing Receivable, after Allowance for Credit Loss	174,497,000				164,676,000				174,497,000	164,676,000
Total loans	174,497,000				164,676,000				174,497,000	164,676,000	132,370,000
Financing Receivable, before Allowance for Credit Loss	174,497,000				164,676,000				174,497,000	164,676,000
Residential Real Estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance				3,219,000				2,822,000	3,219,000	2,822,000	2,621,000
Charge-offs									0	(148,000)	(207,000)
Recoveries									142,000	12,000	31,000
Provision (benefit)									79,000	533,000	377,000
Ending balance	3,440,000				3,219,000				3,440,000	3,219,000	2,822,000
Ending balance: collectively evaluated for impairment	2,803,000				2,357,000				2,803,000	2,357,000	1,815,000
Ending balance: individually evaluated for impairment	637,000				862,000				637,000	862,000	1,007,000
Financing receivables ending balance:
Financing Receivable, Collectively Evaluated for Impairment	1,571,848,000				906,959,000				1,571,848,000	906,959,000	733,809,000
Individually evaluated for impairment	11,228,000				12,706,000				11,228,000	12,706,000	13,684,000
Total loans	1,590,569,000				923,294,000				1,590,569,000	923,294,000	754,329,000
Financing Receivable, before Allowance for Credit Loss	1,590,569,000				923,294,000				1,590,569,000	923,294,000
Home Equity [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance				5,608,000				5,390,000	5,608,000	5,390,000	5,238,000
Charge-offs									(240,000)	(293,000)	(276,000)
Recoveries									318,000	156,000	198,000
Provision (benefit)									(110,000)	355,000	230,000
Ending balance	5,576,000				5,608,000				5,576,000	5,608,000	5,390,000
Ending balance: collectively evaluated for impairment	5,420,000				5,444,000				5,420,000	5,444,000	5,125,000
Ending balance: individually evaluated for impairment	156,000				164,000				156,000	164,000	265,000
Financing receivables ending balance:
Financing Receivable, Collectively Evaluated for Impairment	1,127,963,000				1,085,961,000				1,127,963,000	1,085,961,000	1,045,053,000
Individually evaluated for impairment	4,948,000				5,948,000				4,948,000	5,948,000	6,826,000
Total loans	1,133,798,000				1,092,084,000				1,133,798,000	1,092,084,000	1,052,088,000
Consumer Portfolio Segment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance				$ 422,000				$ 447,000	422,000	447,000	393,000
Charge-offs									(1,598,000)	(1,347,000)	(1,494,000)
Recoveries									787,000	888,000	993,000
Provision (benefit)									785,000	434,000	555,000
Ending balance	396,000				422,000				396,000	422,000	447,000
Ending balance: collectively evaluated for impairment	391,000				414,000				391,000	414,000	430,000
Ending balance: individually evaluated for impairment	5,000				8,000				5,000	8,000	17,000
Financing receivables ending balance:
Financing Receivable, Collectively Evaluated for Impairment	29,663,000				15,901,000				29,663,000	15,901,000	9,573,000
Individually evaluated for impairment	122,000				197,000				122,000	197,000	307,000
Total loans	30,087,000				16,098,000				30,087,000	16,098,000	9,880,000
Financing Receivable, before Allowance for Credit Loss	30,087,000				16,098,000				30,087,000	16,098,000
Financial Asset Acquired with Credit Deterioration [Member]
Financing receivables ending balance:
Financing Receivable, after Allowance for Credit Loss	14,856,000				8,795,000				14,856,000	8,795,000	13,023,000
Financial Asset Acquired with Credit Deterioration [Member] | Commercial and Industrial [Member]
Financing receivables ending balance:
Financing Receivable, after Allowance for Credit Loss	0				0				0	0	0
Financial Asset Acquired with Credit Deterioration [Member] | Commercial Real Estate [Member]
Financing receivables ending balance:
Financing Receivable, after Allowance for Credit Loss	6,174,000				4,991,000				6,174,000	4,991,000	5,978,000
Financial Asset Acquired with Credit Deterioration [Member] | Construction Loans [Member]
Financing receivables ending balance:
Financing Receivable, after Allowance for Credit Loss	0				0				0	0	0
Financial Asset Acquired with Credit Deterioration [Member] | Small Business [Member]
Financing receivables ending balance:
Financing Receivable, after Allowance for Credit Loss	0				0				0	0	0
Financial Asset Acquired with Credit Deterioration [Member] | Residential Real Estate [Member]
Financing receivables ending balance:
Financing Receivable, after Allowance for Credit Loss	7,493,000				3,629,000				7,493,000	3,629,000	6,836,000
Financial Asset Acquired with Credit Deterioration [Member] | Home Equity [Member]
Financing receivables ending balance:
Financing Receivable, after Allowance for Credit Loss	887,000				175,000				887,000	175,000	209,000
Financial Asset Acquired with Credit Deterioration [Member] | Consumer Portfolio Segment [Member]
Financing receivables ending balance:
Financing Receivable, after Allowance for Credit Loss	$ 302,000				$ 0				$ 302,000	$ 0	$ 0
[1]	The amount of net deferred costs on originated loans included in the ending balance was $7.1 million , at December 31, 2019 and 2018 and $6.1 million and at December 31, 2017 . Net unamortized discounts on acquired loans not deemed to be PCI included in the ending balance were $21.6 million , $15.2 million and $9.4 million at December 31, 2019 , 2018 and 2017

Internal Risk Rating Categories

Internal Risk Rating Categories for Commercial Portfolio (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	$ 6,119,185	$ 4,874,718
Commercial and Industrial [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	1,395,036	1,093,629
Commercial Real Estate [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	4,002,359	3,251,248
Construction Loans [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	547,293	365,165
Small Business [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	174,497	164,676
Pass [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	5,848,531	4,695,094
Pass [Member] | Commercial and Industrial [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	1,274,155	1,014,370
Pass [Member] | Commercial Real Estate [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	3,860,555	3,156,989
Pass [Member] | Construction Loans [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	542,608	361,884
Pass [Member] | Small Business [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	171,213	161,851
Potential weakness [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	164,416	74,886
Potential weakness [Member] | Commercial and Industrial [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	63,485	16,860
Potential weakness [Member] | Commercial Real Estate [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	97,268	56,840
Potential weakness [Member] | Construction Loans [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	2,247	298
Potential weakness [Member] | Small Business [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	1,416	888
Definite weakness [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	106,238	101,248
Definite weakness [Member] | Commercial and Industrial [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	57,396	58,909
Definite weakness [Member] | Commercial Real Estate [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	44,536	37,419
Definite weakness [Member] | Construction Loans [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	2,438	2,983
Definite weakness [Member] | Small Business [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	1,868	1,937
Parital loss probable [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	0	3,490
Parital loss probable [Member] | Commercial and Industrial [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	0	3,490
Parital loss probable [Member] | Commercial Real Estate [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	0	0
Parital loss probable [Member] | Construction Loans [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	0	0
Parital loss probable [Member] | Small Business [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	0	0
Definite loss [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	0	0
Definite loss [Member] | Commercial and Industrial [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	0	0
Definite loss [Member] | Commercial Real Estate [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	0	0
Definite loss [Member] | Construction Loans [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	0	0
Definite loss [Member] | Small Business [Member]
Internal risk-rating categories for the Company's commercial portfolio
Financing Receivable, after Allowance for Credit Loss	$ 0	$ 0

Weighted Average FICO Scores &

Weighted Average FICO Scores & weighted Average Combined LTV Ratios (Details) - score	Dec. 31, 2019	Dec. 31, 2018
Residential Portfolio Segment [Member]
Weighted average FICO scores and the weighted average combined LTV Ratio
FICO score (re-scored)	749	749
Financing Receivable With Credit Quality Of Loan Based Upon the Weighted Average Loan-To-Value Ratio	59.00%	58.60%
Home Equity [Member]
Weighted average FICO scores and the weighted average combined LTV Ratio
FICO score (re-scored)	767	767
Financing Receivable With Credit Quality Of Loan Based Upon the Weighted Average Loan-To-Value Ratio	46.60%	49.30%

Summary of Nonaccrual Loans (De

Summary of Nonaccrual Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable Impaired [Line Items]
TDRs on nonaccrual status	$ 24,766	$ 29,348
Financing Receivable, Nonaccrual	45,892	45,413	[1]
Commercial and Industrial [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Nonaccrual	22,574	26,310
Commercial Real Estate [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Nonaccrual	3,016	3,015
Construction Loans [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Nonaccrual	0	311
Small Business [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Nonaccrual	311	235
Residential Real Estate [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Nonaccrual	13,360	8,251
Home Equity [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Nonaccrual	6,570	7,278
Consumer Portfolio Segment [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, Nonaccrual	$ 61	$ 13
[1]	(1) Included in these amounts were $24.8 million and $29.3 million of nonaccruing TDRs at December 31, 2019 and 2018 , respectively.

LOANS, ALLOWANCE FOR LOAN LOS_3

LOANS, ALLOWANCE FOR LOAN LOSSES AND CREDIT QUALITY Foreclosed Residential Real Estate Property (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Foreclosed Residential Real Estate Property [Line Items]
Foreclosed residential real estate property held by the creditor	$ 0	$ 0
Mortgage Loans in Process of Foreclosure, Amount	$ 3,294	$ 3,174

Age Analysis of Past Due Financ

Age Analysis of Past Due Financing receivables (Details) $ in Thousands	Dec. 31, 2019USD ($)loan	Dec. 31, 2018USD ($)loan	Dec. 31, 2017USD ($)
Age Analysis of Past Due Financing Receivables
Number of Loans 30-59 Days | loan	447	400
Number of Loans 60-89 Days | loan	43	56
Number of Loans 90 Days or More | loan	113	110
Number of Loans Total Past Due | loan	603	566
Principal Balance Total Past Due	$ 25,485	$ 46,348
Current	8,848,154	6,859,846
Total loans	8,873,639	6,906,194	$ 6,355,553	[1]
Recorded Investment >90 Days and Accruing	$ 2,157	$ 5
Commercial and Industrial [Member]
Age Analysis of Past Due Financing Receivables
Number of Loans 30-59 Days | loan	1	0
Number of Loans 60-89 Days | loan	2	4
Number of Loans 90 Days or More | loan	5	11
Number of Loans Total Past Due | loan	8	15
Principal Balance Total Past Due	$ 1,336	$ 26,693
Current	1,393,700	1,066,936
Total loans	1,395,036	1,093,629	888,528
Recorded Investment >90 Days and Accruing	$ 0	$ 0
Commercial Real Estate [Member]
Age Analysis of Past Due Financing Receivables
Number of Loans 30-59 Days | loan	7	9
Number of Loans 60-89 Days | loan	1	0
Number of Loans 90 Days or More | loan	8	8
Number of Loans Total Past Due | loan	16	17
Principal Balance Total Past Due	$ 3,922	$ 3,877
Current	3,998,437	3,247,371
Total loans	4,002,359	3,251,248	3,116,561
Recorded Investment >90 Days and Accruing	$ 218	$ 0
Construction Loans [Member]
Age Analysis of Past Due Financing Receivables
Number of Loans 30-59 Days | loan	1	1
Number of Loans 60-89 Days | loan	0	0
Number of Loans 90 Days or More | loan	0	1
Number of Loans Total Past Due | loan	1	2
Principal Balance Total Past Due	$ 560	$ 1,582
Current	546,733	363,583
Total loans	547,293	365,165	401,797
Recorded Investment >90 Days and Accruing	$ 0	$ 0
Small Business [Member]
Age Analysis of Past Due Financing Receivables
Number of Loans 30-59 Days | loan	11	15
Number of Loans 60-89 Days | loan	3	19
Number of Loans 90 Days or More | loan	6	24
Number of Loans Total Past Due | loan	20	58
Principal Balance Total Past Due	$ 967	$ 755
Current	173,530	163,921
Total loans	174,497	164,676	132,370
Recorded Investment >90 Days and Accruing	$ 0	$ 0
Residential Real Estate [Member]
Age Analysis of Past Due Financing Receivables
Number of Loans 30-59 Days | loan	17	23
Number of Loans 60-89 Days | loan	17	6
Number of Loans 90 Days or More | loan	38	25
Number of Loans Total Past Due | loan	72	54
Principal Balance Total Past Due	$ 12,312	$ 8,389
Current	1,578,257	914,905
Total loans	1,590,569	923,294	754,329
Recorded Investment >90 Days and Accruing	$ 1,652	$ 0
Home Equity [Member]
Age Analysis of Past Due Financing Receivables
Number of Loans 30-59 Days | loan	23	22
Number of Loans 60-89 Days | loan	8	12
Number of Loans 90 Days or More | loan	40	29
Number of Loans Total Past Due | loan	71	63
Principal Balance Total Past Due	$ 6,067	$ 4,849
Current	1,127,731	1,087,235
Total loans	1,133,798	1,092,084	1,052,088
Recorded Investment >90 Days and Accruing	$ 265	$ 0
Consumer Portfolio Segment [Member]
Age Analysis of Past Due Financing Receivables
Number of Loans 30-59 Days | loan	387	330
Number of Loans 60-89 Days | loan	12	15
Number of Loans 90 Days or More | loan	16	12
Number of Loans Total Past Due | loan	415	357
Principal Balance Total Past Due	$ 321	$ 203
Current	29,766	15,895
Total loans	30,087	16,098	$ 9,880
Recorded Investment >90 Days and Accruing	22	5
Financial Asset, 30 to 59 Days Past Due [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	7,511	8,402
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial and Industrial [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	253	0
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Real Estate [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	1,690	1,627
Financial Asset, 30 to 59 Days Past Due [Member] | Construction Loans [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	560	1,271
Financial Asset, 30 to 59 Days Past Due [Member] | Small Business [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	837	506
Financial Asset, 30 to 59 Days Past Due [Member] | Residential Real Estate [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	2,237	3,486
Financial Asset, 30 to 59 Days Past Due [Member] | Home Equity [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	1,689	1,331
Financial Asset, 30 to 59 Days Past Due [Member] | Consumer Portfolio Segment [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	245	181
Financial Asset, 60 to 89 Days Past Due [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	4,155	1,854
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial and Industrial [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	323	382
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Real Estate [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	194	0
Financial Asset, 60 to 89 Days Past Due [Member] | Construction Loans [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Small Business [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	15	87
Financial Asset, 60 to 89 Days Past Due [Member] | Residential Real Estate [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	3,055	521
Financial Asset, 60 to 89 Days Past Due [Member] | Home Equity [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	524	855
Financial Asset, 60 to 89 Days Past Due [Member] | Consumer Portfolio Segment [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	44	9
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	13,819	36,092
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial and Industrial [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	760	26,311
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Real Estate [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	2,038	2,250
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Construction Loans [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	0	311
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Small Business [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	115	162
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Residential Real Estate [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	7,020	4,382
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Home Equity [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	3,854	2,663
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Consumer Portfolio Segment [Member]
Age Analysis of Past Due Financing Receivables
Principal Balance Total Past Due	$ 32	$ 13
[1]	The amount of net deferred costs on originated loans included in the ending balance was $7.1 million , at December 31, 2019 and 2018 and $6.1 million and at December 31, 2017 . Net unamortized discounts on acquired loans not deemed to be PCI included in the ending balance were $21.6 million , $15.2 million and $9.4 million at December 31, 2019 , 2018 and 2017

TDR's and Other Pertinent Infor

TDR's and Other Pertinent Information (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Summary of Troubled Debt Restructurings and other pertinent information
TDRs on accrual status	$ 19,599	$ 23,849
TDRs on nonaccrual status	24,766	29,348
Total TDRs	44,365	53,197
Amount of specific reserves included in the allowance for loan loss associated with TDRs:	855	1,079
Additional commitments to lend to a borrower who has been a party to a TDR:	$ 63	$ 982

Modification which Occurred Dur

Modification which Occurred During the Period & Change in Recorded Investment (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)contract	Dec. 31, 2018USD ($)contract	Dec. 31, 2017USD ($)contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts | contract	13	29	54
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 2,189	$ 38,898	$ 8,130
TROUBLED DEBT RESTRUCTURINGS:
Post-Modification Outstanding Recorded Investment	$ 2,231	$ 42,457	$ 8,175
Commercial And Industrial [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts | contract	3	12	12
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 268	$ 35,688	$ 1,787
TROUBLED DEBT RESTRUCTURINGS:
Post-Modification Outstanding Recorded Investment	$ 268	$ 39,224	$ 1,787
Commercial Real Estate [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts | contract	4	3	6
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 819	$ 1,600	$ 2,705
TROUBLED DEBT RESTRUCTURINGS:
Post-Modification Outstanding Recorded Investment	$ 819	$ 1,600	$ 2,705
Small Business [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts | contract	1		9
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 14		$ 369
TROUBLED DEBT RESTRUCTURINGS:
Post-Modification Outstanding Recorded Investment	$ 14		$ 369
Residential Real Estate [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts | contract	3	5	10
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 967	$ 1,048	$ 1,284
TROUBLED DEBT RESTRUCTURINGS:
Post-Modification Outstanding Recorded Investment	$ 1,009	$ 1,071	$ 1,326
Home Equity Line of Credit [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts | contract	2	9	17
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 121	$ 562	$ 1,985
TROUBLED DEBT RESTRUCTURINGS:
Post-Modification Outstanding Recorded Investment	$ 121	$ 562	$ 1,988

Post-modification balance of TD

Post-modification balance of TDRs Listed by type of Modification (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Loans, Allowance for Loan Losses and Credit Quality [Abstract]
Extended maturity	$ 1,565	$ 2,878	$ 5,881
Adjusted interest rate	150	57
Combination rate and maturity	441	38,812	568
Court ordered concession	75	710	1,726
Total	$ 2,231	$ 42,457	$ 8,175

TDR's that have subsequent defa

TDR's that have subsequent default (Details)	12 Months Ended
	Dec. 31, 2019contract	Dec. 31, 2018contract	Dec. 31, 2017USD ($)contract
TROUBLED DEBT RESTRUCTURINGS THAT SUBSEQUENTLY DEFAULTED:
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | contract	0	0	1
Commercial And Industrial [Member]
TROUBLED DEBT RESTRUCTURINGS THAT SUBSEQUENTLY DEFAULTED:
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | $			122,000

Impaired Loan Information by Po

Impaired Loan Information by Portfolio (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	$ 980	$ 1,079	$ 1,342
Related Allowance	980	1,079	1,342
Recorded Investment	49,628	59,060	72,801
Unpaid Principal Balance	68,140	68,514	79,276
Average Recorded Investment	59,682	63,522	76,180
Interest Income Recognized	1,537	1,554	2,026
Commercial and Industrial [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	126	7	10
Commercial Real Estate [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	48	37	42
Construction Loans [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0	0
Small Business [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	8	1	1
Residential Real Estate [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	637	862	1,007
Home Equity [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	156	164	265
Consumer Portfolio Segment [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	5	8	17
With No Related Allowance Recorded [Member]
Impaired loans by loan portfolio
Recorded Investment	39,242	47,900	57,373
Unpaid Principal Balance	56,605	56,125	62,867
Average Recorded Investment	49,077	51,970	60,380
Interest Income Recognized	1,090	1,111	1,449
Related Allowance	0	0	0
With No Related Allowance Recorded [Member] | Commercial and Industrial [Member]
Impaired loans by loan portfolio
Recorded Investment	23,786	28,459	34,267
Unpaid Principal Balance	34,970	35,913	38,329
Average Recorded Investment	27,056	31,117	36,631
Interest Income Recognized	136	142	446
Related Allowance	0	0	0
With No Related Allowance Recorded [Member] | Commercial Real Estate [Member]
Impaired loans by loan portfolio
Recorded Investment	6,213	9,552	13,245
Unpaid Principal Balance	12,101	9,832	14,374
Average Recorded Investment	12,595	10,561	13,683
Interest Income Recognized	523	519	559
Related Allowance	0	0	0
With No Related Allowance Recorded [Member] | Small Business [Member]
Impaired loans by loan portfolio
Recorded Investment	469	358	556
Unpaid Principal Balance	484	439	619
Average Recorded Investment	471	401	569
Interest Income Recognized	22	14	21
Related Allowance	0	0	0
With No Related Allowance Recorded [Member] | Residential Real Estate [Member]
Impaired loans by loan portfolio
Recorded Investment	4,976	4,518	4,264
Unpaid Principal Balance	5,123	4,686	4,397
Average Recorded Investment	5,045	4,597	4,332
Interest Income Recognized	222	212	218
Related Allowance	0	0	0
With No Related Allowance Recorded [Member] | Home Equity [Member]
Impaired loans by loan portfolio
Recorded Investment	3,764	4,957	4,950
Unpaid Principal Balance	3,893	5,199	5,056
Average Recorded Investment	3,869	5,230	5,063
Interest Income Recognized	184	220	198
Related Allowance	0	0	0
With No Related Allowance Recorded [Member] | Consumer Portfolio Segment [Member]
Impaired loans by loan portfolio
Recorded Investment	34	56	91
Unpaid Principal Balance	34	56	92
Average Recorded Investment	41	64	102
Interest Income Recognized	3	4	7
Related Allowance	0	0	0
With Allowance Recorded [Member]
Impaired loans by loan portfolio
Recorded Investment	10,386	11,160	15,428
Unpaid Principal Balance	11,535	12,389	16,409
Average Recorded Investment	10,605	11,552	15,800
Interest Income Recognized	447	443	577
With Allowance Recorded [Member] | Commercial and Industrial [Member]
Impaired loans by loan portfolio
Recorded Investment	670	370	376
Unpaid Principal Balance	670	370	376
Average Recorded Investment	718	385	391
Interest Income Recognized	29	19	19
With Allowance Recorded [Member] | Commercial Real Estate [Member]
Impaired loans by loan portfolio
Recorded Investment	2,124	1,287	3,393
Unpaid Principal Balance	2,124	1,287	3,399
Average Recorded Investment	2,176	1,311	3,447
Interest Income Recognized	122	74	198
With Allowance Recorded [Member] | Small Business [Member]
Impaired loans by loan portfolio
Recorded Investment	68	183	147
Unpaid Principal Balance	105	223	153
Average Recorded Investment	74	225	238
Interest Income Recognized	2	13	14
With Allowance Recorded [Member] | Residential Real Estate [Member]
Impaired loans by loan portfolio
Recorded Investment	6,252	8,188	9,420
Unpaid Principal Balance	7,163	9,217	10,154
Average Recorded Investment	6,326	8,459	9,575
Interest Income Recognized	239	289	284
With Allowance Recorded [Member] | Home Equity [Member]
Impaired loans by loan portfolio
Recorded Investment	1,184	991	1,876
Unpaid Principal Balance	1,382	1,149	2,110
Average Recorded Investment	1,214	1,018	1,916
Interest Income Recognized	52	43	55
With Allowance Recorded [Member] | Consumer Portfolio Segment [Member]
Impaired loans by loan portfolio
Recorded Investment	88	141	216
Unpaid Principal Balance	91	143	217
Average Recorded Investment	97	154	233
Interest Income Recognized	$ 3	$ 5	$ 7

Purchased Credit Impaired Loans

Purchased Credit Impaired Loans - Outstanding/Carrying Balance (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	$ 18,358	$ 9,749
Financing Receivable, after Allowance for Credit Loss	6,119,185	4,874,718
Financial Asset Acquired with Credit Deterioration [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Financing Receivable, after Allowance for Credit Loss	$ 14,856	$ 8,795	$ 13,023

LOANS, ALLOWANCE FOR LOAN LOS_4

LOANS, ALLOWANCE FOR LOAN LOSSES AND CREDIT QUALITY (Details Textual) - USD ($)	3 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Loans, Allowance for Loan Losses and Credit Quality [Abstract]
Unamortized Loan Commitment and Origination fees	$ 7,100,000	$ 7,089,000	$ 6,100,000
Unamortized Discounts or Premiums	$ 21,600,000	15,200,000	$ 9,400,000
Days To Be Termed As Non Accrual Loans	90 days
Significant advanced considered for risk rating change	$ 50,000
TDRs on nonaccrual status	$ 24,766,000	$ 29,348,000

LOANS, ALLOWANCE FOR LOAN LOS_5

LOANS, ALLOWANCE FOR LOAN LOSSES AND CREDIT QUALITY Activity in the Accretable Yield PCI Loans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Loans, Allowance for Loan Losses and Credit Quality [Abstract]
Certain Loans Acquired in Transfer Accounted for as Debt Securities, Accretable Yield, Additions	$ 1,464	$ 0
Certain Loans Acquired in Transfer Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Beginning balance	1,191	1,791
Accretion	(1,751)	(1,135)
Certainloansacquiredinatransfernotaccountedforasdebtsecuritiesaccretableyieldadjustmentchangesinexpectedcashflow	803	310
Reclassification from nonaccretable difference for loans with improved cash flows	227	225
Ending balance	$ 1,934	$ 1,191

BANK PREMISES AND EQUIPMENT (De

BANK PREMISES AND EQUIPMENT (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Total cost	$ 218,921,000	$ 182,787,000
Accumulated depreciation	(95,247,000)	(85,206,000)
Net bank premises and equipment	123,674,000	97,581,000
Depreciation expense	11,400,000	9,100,000	$ 8,500,000
Rental Income, Nonoperating	1,600,000	1,600,000	1,300,000
Operating Leases, Income Statement, Depreciation Expense on Property Subject to or Held-for-lease	1,300,000	1,300,000	$ 939,000
Land [Member]
Property, Plant and Equipment [Line Items]
Total cost	32,619,000	24,502,000
Bank Premises [Member]
Property, Plant and Equipment [Line Items]
Total cost	$ 62,455,000	53,052,000
Bank Premises [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Bank Premises [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	40 years
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Total cost	$ 35,498,000	27,615,000
Leasehold Improvements [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	1 year
Leasehold Improvements [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	27 years
Furniture and Equipment [Member]
Property, Plant and Equipment [Line Items]
Total cost	$ 77,705,000	66,974,000
Furniture and Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	2 years
Furniture and Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	12 years
Equipment Leased to Other Party [Member]
Property, Plant and Equipment [Line Items]
Total cost	$ 10,644,000	$ 10,644,000
Equipment Leased to Other Party [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	7 years

GOODWILL AND IDENTIFIABLE INT_3

GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 506,206	$ 256,105	$ 231,806
Other Intangible Assets	29,286	15,250
Total goodwill and other intangible assets	535,492	271,355
Core Deposits [Member]
Finite-Lived Intangible Assets [Line Items]
Other Intangible Assets	28,016	13,692
Other identifiable Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Other Intangible Assets	$ 1,270	$ 1,558

GOODWILL AND IDENTIFIABLE INT_4

GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS (Details 1) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Balance at beginning of year	$ 256,105	$ 231,806
Acquisitions	250,101	24,299
Balance at end of year	$ 506,206	$ 256,105

GOODWILL AND IDENTIFIABLE INT_5

GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS (Details 2) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 48,583	$ 37,240
Accumulated Amortization	(19,297)	(21,990)
Net Carrying Amount	29,286	15,250
Core Deposits [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	45,245	34,137
Accumulated Amortization	(17,229)	(20,445)
Net Carrying Amount	28,016	13,692
Other intangible assets [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,338	3,103
Accumulated Amortization	(2,068)	(1,545)
Net Carrying Amount	$ 1,270	$ 1,558

GOODWILL AND IDENTIFIABLE INT_6

GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS (Details 3) $ in Thousands	Dec. 31, 2019USD ($)
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2019	$ 6,179
2020	5,315
2021	4,539
2022	3,948
2023	$ 3,162

GOODWILL AND IDENTIFIABLE INT_7

GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS (Details Textual) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 6.8	$ 2.7	$ 3.5
Weighted average amortization period for intangible assets	9 years 9 months 18 days

DEPOSITS (Details)

DEPOSITS (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Banking and Thrift [Abstract]
Deposit Liabilities Reclassified as Loans Receivable	$ 5,000	$ 3,300
Deposit Liabilities, Collateral Issued, Financial Instruments	323,100	356,800
Time Deposits, Fiscal Year Maturity [Abstract]
1 year or less	1,097,407	511,292
Over 1 year to 2 years	204,690	111,487
Over 2 years to 3 years	55,615	41,523
Over 3 years to 4 years	24,038	27,040
Over 4 years to 5 years	13,565	19,761
Time Deposits	$ 1,395,315	$ 711,103
1 year or less (as percent)	78.60%	71.90%
Over 1 years to 2 years (as percent)	14.70%	15.70%
Over 2 years to 3 years (as percent)	4.00%	5.80%
Over 3 years to 4 years (as percent)	1.70%	3.80%
Over 4 years to 5 years (as percent)	1.00%	2.80%
Time Deposits (as percent)	100.00%	100.00%
Deposits over $250,000.00	$ 244,700	$ 104,900

BORROWINGS (FHLB Advances) (Det

BORROWINGS (FHLB Advances) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Disclosure [Abstract]
Federal Home Loan Bank, Advances, Maturities Summary, Due in Next Twelve Months	$ 104,976	$ 147,046
Federal Home Loan Bank, Advances, Activity for Year, Average Interest Rate for Year	1.79%	2.68%
Federal Home Loan Bank, Advances, Maturities Summary, Due in Year Two	$ 10,042	$ 0
Federal Home Loan Bank, Advances, Maturities Summary, Due in Year Three		$ 0
Federal Home Loan Bank, Advances, Maturities Summary, Average Interest Rate, Two to Three Years from Balance Sheet Date		0.00%
Federal Home Loan Bank, Advances, Maturities Summary, Average Interest Rate, One to Two Years from Balance Sheet Date	2.95%	0.00%
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Amount of Advances	$ 115,018	$ 147,046
Federal Home Loan Bank, Advances, Weighted Average Interest Rate	1.89%	2.68%
Debt Instrument, Unamortized Premium	$ 730	$ 760
Total Federal Home Loan Bank Advances	$ 115,748	$ 147,806

BORROWINGS (Long-Term Debt) (De

BORROWINGS (Long-Term Debt) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term Debt	$ 74,906	$ 0
Total Long-Term Borrowings	187,355	110,901
Subordinated Debt	49,601	34,728
Junior Subordinated Debentures [Member] | Capital Trust V Preferred Securities Due in 2037 [Member]
Debt Instrument [Line Items]
Long-term Debt	51,547
Total Long-Term Borrowings	51,507	51,505
Junior Subordinated Debentures [Member] | Slades Ferry Trust I Preferred Securities Due in 2034 [Member]
Debt Instrument [Line Items]
Long-term Debt		10,234
Total Long-Term Borrowings	0
Junior Subordinated Debentures [Member] | Central Bancorp Capital Trust I Securities Due in 2034 [Member]
Debt Instrument [Line Items]
Long-term Debt	5,258
Total Long-Term Borrowings	5,258	5,258
Junior Subordinated Debentures [Member] | Central Bancorp Capital Trust II Securities Due in 2037 [Member]
Debt Instrument [Line Items]
Long-term Debt	6,083
Total Long-Term Borrowings	6,083	6,083
Junior Subordinated Debentures [Member] | East Main Street Trust [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 0	$ 3,093

BORROWINGS (Trust Preferred Sec

BORROWINGS (Trust Preferred Securities) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Junior Subordinated Debentures [Member]
Debt Instrument [Line Items]
Face Amount	$ 61	$ 74
Junior Subordinated Debentures [Member] | Capital Trust V Preferred Securities Due in 2037 [Member]
Debt Instrument [Line Items]
Face Amount	$ 50
Debt Instrument, interest rate, stated rate inclusive of interest rate swap - expired	2.84%
Fixed rate	3.37%
Junior Subordinated Debentures [Member] | Capital Trust V Preferred Securities Due in 2037 [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.48%
Junior Subordinated Debentures [Member] | Slades Ferry Trust I Preferred Securities Due in 2034 [Member]
Debt Instrument [Line Items]
Face Amount	$ 10
Fixed rate	5.59%
Junior Subordinated Debentures [Member] | Slades Ferry Trust I Preferred Securities Due in 2034 [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	2.79%
Junior Subordinated Debentures [Member] | Central Bancorp Capital Trust I Securities Due in 2034 [Member]
Debt Instrument [Line Items]
Face Amount	$ 5.1
Fixed rate	4.33%
Junior Subordinated Debentures [Member] | Central Bancorp Capital Trust I Securities Due in 2034 [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	2.44%
Junior Subordinated Debentures [Member] | Central Bancorp Capital Trust II Securities Due in 2037 [Member]
Debt Instrument [Line Items]
Face Amount	$ 5.9
Junior Subordinated Debentures [Member] | Central Bancorp Capital Trust II Securities Due in 2037 [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.65%
Fixed rate	3.54%
Subordinated Debt [Member] | Subordinated Debentures Due in November 2019 [Member] [Domain]
Debt Instrument [Line Items]
Fixed rate		4.75%
Subordinated Debt [Member] | Subordinated Debentures Due in November 2019 [Member] [Domain] | LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	2.98%

BORROWINGS (Maturities of Long-

BORROWINGS (Maturities of Long-Term Debt) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Long-term Debt, Fiscal Year Maturity [Abstract]
2015	$ 0
2016	0
2017	75,000
2018	0
2019	0
Thereafter	112,888
Total	74,906	$ 0
Long-term Debt, Gross	187,888	35,000
Long-term Debt [Member] | Long-term Debt [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
2015	0
2016	0
2017	75,000
2018	0
2019	0
Thereafter	0
Total	75,000
Junior Subordinated Debentures [Member] | Capital Trust V Preferred Securities Due in 2037 [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
2015	0
2016	0
2017	0
2018	0
2019	0
Thereafter	51,547
Total	51,547
Junior Subordinated Debentures [Member] | Slades Ferry Trust I Preferred Securities Due in 2034 [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
Total		10,234
Junior Subordinated Debentures [Member] | Central Bancorp Capital Trust I Securities Due in 2034 [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
2015	0
2016	0
2017	0
2018	0
2019	0
Thereafter	5,258
Total	5,258
Junior Subordinated Debentures [Member] | Central Bancorp Capital Trust II Securities Due in 2037 [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
2015	0
2016	0
2017	0
2018	0
2019	0
Thereafter	6,083
Total	6,083
Junior Subordinated Debentures [Member] | East Main Street Trust [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
Total	0	$ 3,093
Subordinated Debentures [Member] | Subordinated Debentures Due August 27, 2018 [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
2015	0
2016	0
2017	0
2018	0
2019	0
Subordinated Debentures [Member] | Subordinated note due 2029 [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
Thereafter	50,000
Total	$ 50,000

BORROWINGS (Details Textual)

BORROWINGS (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Operating Leases, Income Statement, Depreciation Expense on Property Subject to or Held-for-lease	$ 1,300,000	$ 1,300,000	$ 939,000
Subordinated Debt	49,601,000	34,728,000
Long-term Debt, Gross	187,888,000	35,000,000
Interest Expense, Long-term Debt	8,200,000	4,200,000	3,900,000
Loans Pledged as Collateral	$ 2,500,000,000	$ 1,600,000,000
Federal Home Loan Bank Advances Weighted Average Interest Rate inclusive of Swaps	1.88%	2.55%
Securities Sold under Agreements to Repurchase	$ 0	$ 0
Short-term Debt	50,000,000
Customer Repurchase Agreements and other short-term borrowings		162,700,000
Interest expense on short-term borrowings	104,000	248,000	$ 257,000
Long-term Debt	74,906,000	0
Total Long-Term Borrowings	187,355,000	110,901,000
Parent Company [Member]
Debt Instrument [Line Items]
Subordinated Debt		35,000,000
Federal Home Loan Bank Advances [Member]
Debt Instrument [Line Items]
Federal home loan bank unused remaining available borrowing capacity	1,600,000,000	$ 953,500,000
Line of credit maximum borrowing capacity	$ 5,000,000
Short-term Debt [Member] | Short-term Debt [Member]
Debt Instrument [Line Items]
Fixed rate	1.15%

EARNINGS PER SHARE (Details)

EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share [Abstract]
Net income	$ 47,477	$ 51,845	$ 30,628	$ 35,225	$ 29,934	$ 33,015	$ 31,118	$ 27,555	$ 165,175	$ 121,622	$ 87,204
Weighted Average Shares (in shares)
Basic Shares (in shares)	34,374,953	34,361,176	34,313,492	28,106,184	27,815,437	27,537,841	27,526,653	27,486,573	32,810,433	27,592,380	27,294,028
Effect of dilutive securities (in shares)	46,245	39,390	41,878	54,466	58,576	63,499	54,525	67,381	45,801	61,428	78,076
Weighted average common shares (diluted) (in shares)	34,421,198	34,400,566	34,355,370	28,160,650	27,874,013	27,601,340	27,581,178	27,553,954	32,856,234	27,653,808	27,372,104
Net Income Available to Common Shareholders per Share (in dollars per share)
Basic EPS (in dollars per share)	$ 1.38	$ 1.51	$ 0.89	$ 1.25	$ 1.08	$ 1.20	$ 1.13	$ 1	$ 5.03	$ 4.41	$ 3.19
Effect of Dilutive Securities (in dollars per share)									0	(0.01)	0
Diluted EPS (in dollars per share)	$ 1.38	$ 1.51	$ 0.89	$ 1.25	$ 1.07	$ 1.20	$ 1.13	$ 1	$ 5.03	$ 4.40	$ 3.19

EARNINGS PER SHARE (Details 1)

EARNINGS PER SHARE (Details 1) - shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Performance Shares [Member]
Details of anti dilutive options to purchase common stock
Stock options	0	0	0
Stock options [Member]
Details of anti dilutive options to purchase common stock
Stock options	0	0	103

CUMULATIVELY GRANTED AWARDS (De

CUMULATIVELY GRANTED AWARDS (Details)	Dec. 31, 2019shares
2005 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized Stock Awards	1,650,000
Cumulative Granted, Net of Forfeitures and Expirations	1,197,639
Authorized but Unissued	452,361
2005 Plan [Member] | Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cumulative Granted, Net of Forfeitures and Expirations	387,258
2005 Plan [Member] | Restricted stock awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cumulative Granted, Net of Forfeitures and Expirations	810,381
2010 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized Stock Awards	314,600
Cumulative Granted, Net of Forfeitures and Expirations	139,745
Authorized but Unissued	0	[1]
2010 Plan [Member] | Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cumulative Granted, Net of Forfeitures and Expirations	46,500
2010 Plan [Member] | Restricted stock awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cumulative Granted, Net of Forfeitures and Expirations	93,245
Two Thousand Eighteen Nonemployee Director Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized Stock Awards	300,000
Cumulative Granted, Net of Forfeitures and Expirations	12,500
Authorized but Unissued	287,500	[1]
Two Thousand Eighteen Nonemployee Director Stock Plan [Member] | Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cumulative Granted, Net of Forfeitures and Expirations	0
Two Thousand Eighteen Nonemployee Director Stock Plan [Member] | Restricted stock awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cumulative Granted, Net of Forfeitures and Expirations	12,500
[1]	The Company may award up to a total of 300,000 shares from the 2018 Plan, inclusive of 174,855 shares that were Authorized but Unissued in the 2010 Plan, and were transferred from the 2010 Plan to the 2018 Plan. Due to this transfer, there are no available shares remaining to be issued from the 2010 Plan.

PRE TAX EXPENSE (Details 1)

PRE TAX EXPENSE (Details 1) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock based award expense		$ 4,403	$ 4,225	$ 3,333
Related tax benefits recognized in earnings		1,238	1,188	1,362
Stock options [Member] | Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock based award expense	[1]	23	66	76
Restricted stock awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock based award expense	[2]	3,679	3,299	2,730
Restricted stock awards [Member] | Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock based award expense	[1]	$ 701	$ 860	$ 527
[1]	Expense related to awards issued to directors is recognized as directors’ fees within other noninterest expense.
[2]	Inclusive of compensation expense associated with time-vested and performance-based restricted stock awards.

STOCK OPTION AWARDS DURING PERI

STOCK OPTION AWARDS DURING PERIOD (Details 3) - Stock options [Member] - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average remaining recognition period (years)	0 years
Shares granted	0
Weighted average grant date fair value of options granted (per share)	$ 0	$ 13.46	$ 12.43
Options Granted Date Three [Member] | 2010 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted		5,000
Vesting period		21 months
Investment Options, Expiration Date		Apr. 3, 2028
Expected volatility		21.15%
Expected life (years)		5 years 6 months
Expected dividend yield		1.94%
Risk free interest rate		2.62%
Weighted average grant date fair value of options granted (per share)		$ 13.46
Options Granted Date Two [Member] | 2010 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted			5,000
Vesting period			14 months
Investment Options, Expiration Date			Nov. 7, 2027
Expected volatility			20.80%
Expected life (years)			5 years 6 months
Expected dividend yield			1.87%
Risk free interest rate			2.02%
Weighted average grant date fair value of options granted (per share)			$ 12.43

RELEVANT STOCK OPTION INFORMATI

RELEVANT STOCK OPTION INFORMATION (Details 4) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash received from stock option exercises	$ 281	$ 184	$ 214
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of stock options vested based on grant date fair value	21	85	72
Intrinsic value of stock options exercised	883	1,525	1,082
Cash received from stock option exercises	396	1,024	918
Share-based Payment Arrangement, Exercise of Option, Tax Benefit	$ 248	$ 429	$ 442
Weighted average grant date fair value of options granted (per share)	$ 0	$ 13.46	$ 12.43

STOCK OPTION ROLLFORWARD (Detai

STOCK OPTION ROLLFORWARD (Details 5) - Stock options [Member] - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
		Dec. 31, 2019		Dec. 31, 2018	Dec. 31, 2017
Stock Option Awards, Outstanding (in shares):
Balance outstanding at beginning of period		54,500
Granted		0
Exercised		(16,000)
Forfeited		0
Expired		0
Balance outstanding at end of period		38,500	[1]	54,500
Options outstanding and expected to vest at December 31, 2019	[2]	38,500
Options exercisable at December 31, 2019	[3]	36,834
Weighted Average Exercise Price, Outstanding (in usd per share):
Balance outstanding at beginning of period		$ 37.28
Granted		0
Exercised		24.76
Forfeited		0
Expired		0
Balance outstanding at end of period		42.49		$ 37.28
Options outstanding and expected to vest at December 31, 2019		42.49
Options exercisable at December 31, 2019		$ 41.21
Balance at December 31, 2019, Weighted average remaining contractual term (years)		4 years
Options outstanding and expected to vest at December 31, 2019, Weighted Average Remaining Contractual Term (years)		4 years
Options exercisable at December 31, 2019, Weighted Average Remaining Contractual Term (years)		3 years 9 months 21 days
Balance at December 31, 2019, Aggregate Intrinsic Value	[4]	$ 1,584
Options outstanding and expected to vest at December 31, 2019, Aggregate Intrinsic Value	[4]	1,584
Options exercisable at December 31, 2019, Aggregate Intrinsic Value	[4]	$ 1,563
Stock Option Awards, Nonvested (in shares)
Balance nonvested at beginning of period		3,332
Granted		0
Vested		(1,666)
Forfeited		0
Expired		0
Balance nonvested at end of period		1,666		3,332
Weighted Average Grant Date Fair Value, Nonvested (in dollars per share):
Balance nonvested at beginning of period		$ 12.94
Granted		0		$ 13.46	$ 12.43
Vested		12.43
Forfeited		0
Expired		0
Balance nonvested at end of period		$ 13.46		$ 12.94
Unrecognized compensation cost		$ 0
Weighted average remaining recognition period (years)		0 years
[1]	Inclusive of 22,500 stock options outstanding to Directors.
[2]	Inclusive of 22,500 vested stock options and expected to vest to Directors.
[3]	Inclusive of 20,834 vested stock options outstanding to Directors.
[4]	The aggregate intrinsic value represents the total pre-tax intrinsic value, based on the average of the high price and low price at which the Company’s common stock traded on December 31, 2019 of $83.64 , which would have been received by in-the-money option holders had they all exercised their options as of that date.

RSA GRANTS (Details 6)

RSA GRANTS (Details 6) - $ / shares		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restricted stock awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value		$ 83.16
Restricted stock awards [Member] | Employee Stock Plan [Member] | 2/21/2019 | Ratably Over Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted		43,250
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	[1]	$ 83.87
Vesting terms		Ratably over 5 years from grant date
Restricted stock awards [Member] | Employee Stock Plan [Member] | 3/15/2019 | Ratably Over Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted		600
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	[1]	$ 79.55
Vesting terms		Ratably over 5 years from grant date
Restricted stock awards [Member] | Employee Stock Plan [Member] | 4/1/2019 | Ratably Over Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted		1,090
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	[1]	$ 82.62
Vesting terms		Ratably over 3 years from grant date
Restricted stock awards [Member] | Employee Stock Plan [Member] | 5/21/2019 | Ratably Over Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted		6,500
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	[1]	$ 77.08
Vesting terms		Immediately upon grant date
Restricted stock awards [Member] | Employee Stock Plan [Member] | 2/15/2018 | Ratably Over Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted			39,950
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	[1]		$ 71.75
Vesting terms			Ratably over 5 years from grant date
Restricted stock awards [Member] | Employee Stock Plan [Member] | 2/27/2018 | Ratably Over Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted			1,150
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	[1]		$ 72.60
Vesting terms			Ratably over 5 years from grant date
Restricted stock awards [Member] | Employee Stock Plan [Member] | 5/22/2018 | Ratably Over Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted			6,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	[1]		$ 76.58
Vesting terms			Immediately upon grant date
Restricted stock awards [Member] | Employee Stock Plan [Member] | 11/15/2018 | Ratably Over Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted			560
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	[1]		$ 77.78
Vesting terms			Ratably over 5 years from grant date
Restricted stock awards [Member] | Employee Stock Plan [Member] | 2/13/2017 | Ratably Over Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted				1,200
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	[1]			$ 62.53
Vesting terms				Ratably over 5 years from grant date
Restricted stock awards [Member] | Employee Stock Plan [Member] | 2/16/2017 | Ratably Over Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted				34,150
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	[1]			$ 63.10
Vesting terms				Ratably over 5 years from grant date
Restricted stock awards [Member] | Employee Stock Plan [Member] | 3/31/2017 | Ratably Over Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted				500
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	[1]			$ 65.63
Vesting terms				Ratably over 5 years from grant date
Restricted stock awards [Member] | Employee Stock Plan [Member] | 4/3/2017 | At The End of Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted				1,500
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	[1]			$ 64.14
Vesting terms	[2]			Once on November 30, 2017 (2)
Restricted stock awards [Member] | Employee Stock Plan [Member] | 5/15/2017 | At The End of Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted				1,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	[1]			$ 64.03
Vesting terms				Ratably over 5 years from grant date
Restricted stock awards [Member] | Employee Stock Plan [Member] | 6/15/2017 | At The End of Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted				950
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	[1]			$ 66.18
Vesting terms				Ratably over 5 years from grant date
Restricted stock awards [Member] | Non Employee Director Stock Plan Member | 5/15/2018 | At The End of Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted			530
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	[1]		$ 74
Vesting terms			Ratably over 5 years from grant date
Restricted stock awards [Member] | Non Employee Director Stock Plan Member | 5/23/2017 | At The End of Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted				7,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	[1]			$ 61.95
Vesting terms	[3]			At the end of 5 years from grant date (3)
Performance Shares [Member] | Employee Stock Plan [Member] | 2/21/2019 | At The End of Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted		15,900
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	[1]	$ 83.87
Vesting terms		The earlier of: the date on which it is determined if the performance goal has been achieved; or, March 31, 2022.
Performance Shares [Member] | Employee Stock Plan [Member] | 2/27/2018 | At The End of Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted			16,300
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	[1]		$ 71.75
Vesting terms			The earlier of: the date on which it is determined if the performance goal has been achieved; or, March 31, 2021.
Performance Shares [Member] | Employee Stock Plan [Member] | 2/13/2017 | At The End of Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted				14,400
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	[1]			$ 63.10
Vesting terms				The earlier of: the date on which it is determined if the performance goal has been achieved; or, March 31, 2020.
[1]	The fair value of the restricted stock awards are based upon the average of the high and low prices at which the Company’s common stock traded on the date of grant. The holders of time-vested restricted stock awards participate fully in the rewards of stock ownership of the Company, including voting and dividend rights. The holders of performance-based restricted stock awards do not participate in the rewards of stock ownership of the Company until vested. The holders of all restricted stock awards are not required to pay any consideration to the Company for the awards.
[2]	This restricted stock grant fully vested upon an employee's termination, on November 30, 2017.
[3]	These restricted stock grants will vest at the end of a five year period, or earlier if the director ceases to be a director for any reason other than cause, such as, for example, by retirement.

FV OF RSA VESTS (Details 7)

FV OF RSA VESTS (Details 7) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restricted stock awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of restricted stock awards upon vesting	$ 6,005	$ 6,277	$ 5,717

RSA ROLLFORWARD (Details 8)

RSA ROLLFORWARD (Details 8) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)$ / sharesshares
Oustanding (in shares):
Beginning balance	153,459
Ending balance	147,184
Restricted stock awards [Member]
Oustanding (in shares):
Beginning balance	202,106
Granted	67,340
Vested/Released	(74,272)
Forfeited	(1,390)
Ending balance	193,784	[1]
Weighted Average Grant Price (in usd per share):
Beginning balance | $ / shares	$ 55.62
Granted | $ / shares	83.16
Vested/Released | $ / shares	49.56
Forfeited | $ / shares	64.76
Ending balance | $ / shares	$ 67.48
Unrecognized compensation cost (inclusive of directors’ fees) | $	$ 8,098
Weighted average remaining recognition period (years)	2 years 11 months 26 days
[1]	Inclusive of 17,925 restricted stock awards outstanding to Directors.

STOCK BASED COMPENSATION (Detai

STOCK BASED COMPENSATION (Details Textual) - $ / shares		12 Months Ended
		Dec. 31, 2019		Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number		147,184		153,459
Share Based Compensation Arrangement By Share Based Payment Award Options Price Per Share Common Stock Average High And Low Price Intrinsic Value		$ 83.64
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number		38,500	[1]	54,500
Options outstanding and expected to vest at December 31, 2019	[2]	38,500
Options exercisable at December 31, 2019	[3]	36,834
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares		1,666		3,332
Weighted average remaining recognition period (years)		0 years
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number		193,784	[4]	202,106
Weighted average remaining recognition period (years)		2 years 11 months 26 days
Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number		22,500
Options outstanding and expected to vest at December 31, 2019	[1]	22,500
Options exercisable at December 31, 2019	[1]	20,834
Director [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number		17,925
Two Thousand Eighteen Nonemployee Director Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized		300,000
Two Thousand Five Amended and Restated Employee Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized		1,650,000
Two Thousand Ten Nonemployee Director Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized		314,600
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant		174,855
[1]	Inclusive of 22,500 stock options outstanding to Directors.
[2]	Inclusive of 22,500 vested stock options and expected to vest to Directors.
[3]	Inclusive of 20,834 vested stock options outstanding to Directors.
[4]	Inclusive of 17,925 restricted stock awards outstanding to Directors.

Derivatives and Hedging Activ_3

Derivatives and Hedging Activities (Derivative Positions for Interest Rate Swaps which Qualify as Hedges) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes
Amortization Of Deferred Hedge Gains Losses	$ 0	$ 231,000	$ 244,000
Notional amount of fair value hedged derivative	$ 0	$ 0	$ 0
Interest rate swaps on borrowings [Member]
Derivatives, Fair Value [Line Items]
Derivative, Average Remaining Maturity	2 years 2 months 4 days	3 years 2 months 4 days
Derivative, Average Variable Interest Rate	1.90%	2.74%
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes
Fair Value	$ 140,000	$ 2,282,000
Derivative, Notional Amount	$ 75,000,000	$ 75,000,000
Derivative, Average Fixed Interest Rate	1.53%	1.53%
Interest rate swaps on loans [Member]
Derivatives, Fair Value [Line Items]
Derivative, Average Remaining Maturity	3 years 7 months 28 days	4 years 6 months 7 days
Derivative, Average Variable Interest Rate	1.76%	2.57%
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes
Fair Value	$ 12,907,000	$ 2,938,000
Derivative, Notional Amount	$ 450,000,000	$ 250,000,000
Derivative, Average Fixed Interest Rate	2.37%	2.67%
Interest rate collars on loans [Member]
Derivatives, Fair Value [Line Items]
Derivative, Average Remaining Maturity	3 years 7 months 28 days	4 years 2 months 1 day
Derivative, Average Variable Interest Rate	1.76%	2.47%
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes
Fair Value	$ 9,896,000	$ 3,344,000
Derivative, Notional Amount	$ 400,000,000	$ 250,000,000
Derivative, Cap Interest Rate	2.73%	3.02%
Derivative, Floor Interest Rate	2.20%	2.51%
Interest Rate Swap [Member]
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes
Fair Value	$ 22,943,000	$ 8,564,000
Derivative, Notional Amount	$ 925,000,000	$ 575,000,000

Derivatives and Hedging Activ_4

Derivatives and Hedging Activities (Customer Related Derivative Positions - Not Designated as Hedges) (Details) - Not Designated as Hedging Instrument [Member] $ in Thousands	Dec. 31, 2019USD ($)position	Dec. 31, 2018USD ($)position
Receive fixed, pay variable | Loan level swaps
Summary of customer related derivative positions, not designated as hedging
Number of Positions (1) | position	299	235
Less than 1 year	$ 156,690	$ 50,702
Less than 2 years	125,203	124,222
Less than 3 years	85,603	97,904
Less than 4 years	165,599	47,308
Thereafter	1,044,315	631,471
Derivative, Notional Amount	1,577,410	951,607
Fair Value	$ 48,596	$ (2,907)
Pay fixed, receive variable | Loan level swaps
Summary of customer related derivative positions, not designated as hedging
Number of Positions (1) | position	290	220
Less than 1 year	$ 156,690	$ 50,702
Less than 2 years	125,203	124,222
Less than 3 years	85,603	97,904
Less than 4 years	165,599	47,308
Thereafter	1,044,315	631,471
Derivative, Notional Amount	1,577,410	951,607
Fair Value	$ (48,591)	$ 2,903
Buys foreign currency, sells U.S. currency | Foreign exchange contracts
Summary of customer related derivative positions, not designated as hedging
Number of Positions (1) | position	40	27
Less than 1 year	$ 91,434	$ 60,297
Less than 2 years		3,505
Derivative, Notional Amount	91,434	63,802
Fair Value	$ (81)	$ (1,404)
Buys U.S. currency, sells foreign currency | Foreign exchange contracts
Summary of customer related derivative positions, not designated as hedging
Number of Positions (1) | position	40	27
Less than 1 year	$ 91,434	$ 60,297
Less than 2 years		3,505
Derivative, Notional Amount	91,434	63,802
Fair Value	$ 123	$ 1,434

Derivatives and Hedging Activ_5

Derivatives and Hedging Activities (FV of Derivative Financial Instruments and Classification on Balance Sheet) (Details) - USD ($) $ in Thousands		Dec. 31, 2019		Dec. 31, 2018
Fair value of derivative financial instruments as well as their classification on the balance sheet
Total		$ 76,705		$ 26,113
Total		53,715		17,523
Other Assets [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value	[1]	55,245		17,355
Total	[1]			26,310
Other Liabilities [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value	[2]	53,726		17,132
Total	[2]	53,923		17,523
Interest rate derivatives | Derivatives designated as hedges: [Member] | Other Assets [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Interest Rate Derivative Assets, at Fair Value	[1]	23,140		8,955
Interest rate derivatives | Derivatives designated as hedges: [Member] | Other Liabilities [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Interest rate derivatives	[2]	197		391
Loan level swaps | Other Assets [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Total	[1]	52,374		15,580
Loan level swaps | Other Liabilities [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Total	[2]	52,369		15,584
Foreign exchange contracts | Other Assets [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Total	[1]	1,191		1,578
Foreign exchange contracts | Other Liabilities [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Total	[2]	1,149		1,548
Mortgage Derivatives | Derivatives not designated as hedges: [Member] | Other Assets [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Interest rate lock commitments	[1]	1,680		91
Forward sale hedge commitments	[1]	0		106
Derivative Instrument Not Designated as a Hedge, Forward Sale Hedge Commitment, Asset at Fair Value	[1]	0		0
Mortgage Derivatives | Derivatives not designated as hedges: [Member] | Other Liabilities [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Interest rate lock commitments	[2]	0		0
Forward sale hedge commitments	[2]	12		0
Derivative Instrument Not Designated as a Hedge, Forward Sale Hedge Commitment, Liability at Fair Value	[2]	196		0
Derivative instruments | Fair Value, Recurring [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Total		78,385		26,310
Derivative instruments | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value of derivative financial instruments as well as their classification on the balance sheet
Total		$ 78,385	[1]	$ 26,310
[1]	All asset derivatives are located in other assets on the balance sheet
[2]	All liability derivatives are located in other liabilities on the balance sheet

Derivatives and Hedging Activ_6

Derivatives and Hedging Activities (Derivative Financial Instruments included in OCI and Current Earnings) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Portion Attributable to Parent			$ 443
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	$ 2,346	$ 1,000	(441)
Derivatives not designated as hedges: [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other income	1,296	56	(54)
Other Expense [Member] | Derivatives not designated as hedges: [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other income	(18)	(29)	(21)
Other Income [Member] | Derivatives not designated as hedges: [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other income	39	46	6
Mortgage banking income | Derivatives not designated as hedges: [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Increase Decrease In Fair Value Of Unhedged Derivative Instruments Relating To Residential Loans	1,275	39	(39)
Derivatives designated as hedges: [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Portion Attributable to Parent	$ 10,331	$ 4,829	$ 443

Derivatives and Hedging Activ_7

Derivatives and Hedging Activities (Textual) (Details) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Derivative, Net Liability Position, Aggregate Fair Value		$ 26,000,000	$ 176,000
Derivative, Collateral, Right to Reclaim Cash		25,493,000	173,000
Increase (Decrease) in Loans Held-for-sale		822,000	(51,000)	$ (113,000)
Net amortization income		0	231,000	244,000
Exposure to Institutional Counterparties		$ 25,400,000	18,400,000
Maximum length of time Company is currently hedging its exposure		4 years 10 months 24 days
Customer related positions		$ 51,000,000	6,400,000
Gain (Loss) on Sales of Loans, Net	$ 951,000	13,200,000	$ 3,600,000	$ 4,700,000
Fair Value Hedges, Net		0
Interest Income [Member]
Derivative [Line Items]
Interest expense		6,000,000
Interest Expense [Member]
Derivative [Line Items]
Interest expense		150,000
CME [Member]
Derivative [Line Items]
Derivative, Collateral, Right to Reclaim Cash		$ 1,300,000

BALANCE SHEET OFFSETTING (Detai

BALANCE SHEET OFFSETTING (Details) - USD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018
Offsetting Liabilities [Line Items]
Total		$ 76,705	$ 26,113
Derivative Asset, Collateral, Obligation to Return Cash, Offset		0	0
Derivative Asset		76,705	26,113
Derivative, Collateral, Obligation to Return Securities	[1]	24,882	6,556
Derivative, Collateral, Obligation to Return Cash		0	(8,528)
Derivative Asset, Fair Value, Amount Offset Against Collateral		51,823	11,029
Total		53,715	17,523
Derivative Liability, Collateral, Right to Reclaim Cash, Offset		0	0
Derivative Liability		53,715	17,523
Derivative, Collateral, Right to Reclaim Securities	[1]	24,882	6,556
Derivative, Collateral, Right to Reclaim Cash		25,493	173
Derivative Liability, Fair Value, Amount Offset Against Collateral		3,340	10,794
Interest Rate Swap [Member]
Offsetting Liabilities [Line Items]
Derivative Asset, Collateral, Obligation to Return Cash, Offset		0	0
Derivative Asset		23,140	8,955
Derivative, Collateral, Obligation to Return Securities		23,140	391
Derivative, Collateral, Obligation to Return Cash		0	5,527
Derivative Asset, Fair Value, Amount Offset Against Collateral		0	3,037
Derivative Liability, Collateral, Right to Reclaim Cash, Offset		0	0
Derivative Liability		197	391
Derivative, Collateral, Right to Reclaim Securities		0	391
Derivative, Collateral, Right to Reclaim Cash		197	0
Derivative Liability, Fair Value, Amount Offset Against Collateral		0	0
Loan level swaps
Offsetting Liabilities [Line Items]
Derivative Asset, Collateral, Obligation to Return Cash, Offset		0	0
Derivative Asset		52,374	15,580
Derivative, Collateral, Obligation to Return Securities		1,742	6,165
Derivative, Collateral, Obligation to Return Cash		0	3,001
Derivative Asset, Fair Value, Amount Offset Against Collateral		50,632	6,414
Derivative Liability, Collateral, Right to Reclaim Cash, Offset		0	0
Derivative Liability		52,369	15,584
Derivative, Collateral, Right to Reclaim Securities		24,882	6,165
Derivative, Collateral, Right to Reclaim Cash		25,296	173
Derivative Liability, Fair Value, Amount Offset Against Collateral		2,191	9,246
Foreign Exchange Contract [Member]
Offsetting Liabilities [Line Items]
Derivative Asset, Collateral, Obligation to Return Cash, Offset		0	0
Derivative Asset		1,191	1,578
Derivative, Collateral, Obligation to Return Securities		0	0
Derivative, Collateral, Obligation to Return Cash		0	0
Derivative Asset, Fair Value, Amount Offset Against Collateral		1,191	1,578
Derivative Liability, Collateral, Right to Reclaim Cash, Offset		0	0
Derivative Liability		1,149	1,548
Derivative, Collateral, Right to Reclaim Securities		0	0
Derivative, Collateral, Right to Reclaim Cash		0	0
Derivative Liability, Fair Value, Amount Offset Against Collateral		1,149	1,548
Other Assets [Member]
Offsetting Liabilities [Line Items]
Total	[2]		26,310
Other Assets [Member] | Loan level swaps
Offsetting Liabilities [Line Items]
Total	[2]	52,374	15,580
Other Assets [Member] | Foreign Exchange Contract [Member]
Offsetting Liabilities [Line Items]
Total	[2]	1,191	1,578
Other Assets [Member] | Designated as Hedging Instrument [Member] | Interest Rate Swap [Member]
Offsetting Liabilities [Line Items]
Interest Rate Derivative Assets, at Fair Value	[2]	23,140	8,955
Other Liabilities [Member]
Offsetting Liabilities [Line Items]
Total	[3]	53,923	17,523
Other Liabilities [Member] | Loan level swaps
Offsetting Liabilities [Line Items]
Total	[3]	52,369	15,584
Other Liabilities [Member] | Foreign Exchange Contract [Member]
Offsetting Liabilities [Line Items]
Total	[3]	1,149	1,548
Other Liabilities [Member] | Designated as Hedging Instrument [Member] | Interest Rate Swap [Member]
Offsetting Liabilities [Line Items]
Interest rate derivatives	[3]	$ 197	$ 391
[1]	Reflects offsetting derivative positions with the same counterparty.
[2]	All asset derivatives are located in other assets on the balance sheet
[3]	All liability derivatives are located in other liabilities on the balance sheet

INCOME TAXES (Details)

INCOME TAXES (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current expense
Federal									$ 27,980	$ 25,129	$ 28,852
State									14,359	13,672	9,278
Total current expense									42,339	38,801	38,130
Deferred expense (benefit)
Federal									9,080	(3,080)	7,953
State									1,514	(1,417)	1,258
Total deferred expense (benefit)									10,594	(4,497)	9,211
Total expense	$ 14,368	$ 17,036	$ 10,007	$ 11,522	$ 8,258	$ 9,969	$ 9,249	$ 6,828	$ 52,933	$ 34,304	$ 47,341

INCOME TAXES (Details 1)

INCOME TAXES (Details 1) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
Computed statutory federal income tax provision									$ 45,803	$ 32,744	$ 47,091
State taxes, net of federal tax benefit									12,262	9,633	6,817
Merger and other related costs (non-deductible)									582	130	213
Change in valuation allowance									17	49	31
Effective Income Tax Rate Reconciliation, Revaluation of Net Deferred Tax Assets									0	0	1,895
New Markets Tax Credits									(2,675)	(3,960)	(3,960)
Increase in cash surrender value of life insurance									(1,144)	(1,160)	(1,445)
Effective Income Tax Rate Reconciliation, Tax Credit, Investment, Amount									(1,696)	(1,030)	(1,253)
Stock-based compensation									(824)	(885)	(1,258)
Nontaxable interest, net									(757)	(566)	(987)
Other, net									1,365	(651)	197
Total expense	$ 14,368	$ 17,036	$ 10,007	$ 11,522	$ 8,258	$ 9,969	$ 9,249	$ 6,828	$ 52,933	$ 34,304	$ 47,341
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Computed statutory federal income tax provision									21.00%	21.00%	35.00%
State taxes, net of federal tax benefit									5.63%	6.18%	5.07%
Merger and other related costs (non-deductible)									0.27%	0.08%	0.16%
Change in valuation allowance									0.01%	0.03%	0.02%
Effective Income Tax Rate Reconciliation, Revaluation of Net Deferred Tax Asset, Percent									0.00%	0.00%	1.41%
New Markets Tax Credits									(1.23%)	(2.54%)	(2.94%)
Increase in cash surrender value of life insurance									(0.52%)	(0.74%)	(1.07%)
Effective Income Tax Rate Reconciliation, Tax Credit, Investment, Percent									(0.78%)	(0.66%)	(0.93%)
Stock-based compensation									(0.38%)	(0.57%)	(0.94%)
Nontaxable interest, net									(0.35%)	(0.36%)	(0.73%)
Other, net									0.63%	(0.42%)	0.15%
Total expense									24.28%	22.00%	35.20%

INCOME TAXES (Details 2)

INCOME TAXES (Details 2) - USD ($) $ in Thousands	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Deferred tax assets
Accrued expenses not deducted for tax purposes	$ 13,855		$ 11,922
Allowance for loan losses	18,993		17,764
Employee and director equity compensation	1,708		1,636
Loan basis difference fair value adjustment	6,804		4,761
Deferred Tax Assets, Operating Loss Carryforwards	2,546		170
Deferred Tax Assets, Unrealized Losses on Available-for-Sale Securities, Gross	0		1,850
Deferred Tax Asset, Operating Lease Liability	16,393
Operating Lease, Liability	(58,302)	$ (34,100)	0
Other	1,311		1,561
Gross deferred tax assets	61,610		39,664
Deferred Tax Assets, Valuation Allowance	(187)		(170)
Deferred Tax Assets, Net of Valuation Allowance	61,423		39,494
Deferred tax liabilities
Core deposit and other intangibles	5,802		3,803
Deferred loan fees, net	4,944		4,759
Deferred Tax Liabilities, Derivatives	6,461		2,413
Fixed assets	8,194		5,259
Goodwill	10,645		10,388
Deferred Tax Liabilities, Prepaid Expenses	3,487		3,483
Deferred Tax Liabilities, Leasing Arrangements	15,911		0
Other	3,965		1,139
Gross deferred tax liabilities	59,409		31,244
Total net deferred tax asset	$ 2,014		$ 8,250

INCOME TAXES (Details 3)

INCOME TAXES (Details 3) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning Balance	$ 215	$ 142
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions	127
Increase for current year tax positions	444	73
Ending Balance	$ 532	$ 215

INCOME TAXES (Details Textual)

INCOME TAXES (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Tax Expense related to a change in tax law	$ 0	$ 0	$ 466,000
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount	116,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	(10,000)	24,000	$ 18,000
Deferred Tax Assets, Operating Loss Carryforwards	$ 2,546,000	$ 170,000
Computed statutory federal income tax provision	21.00%	21.00%	35.00%
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	$ 43,000	$ 53,000	$ 29,000
Operating Loss Carryforwards	11,200,000
Net Deferred Tax Asset [Member]
Tax Expense related to a change in tax law		$ 71,000	1,900,000
Investments in Low Income Housing Projects [Member]
Tax Expense related to a change in tax law			$ 466,000
Deferred Tax Assets, Operating Loss Carryforwards	$ 187,000

LOW INCOME HOUSING PROJECT IN_3

LOW INCOME HOUSING PROJECT INVESTMENTS Low Income Housing Project Investments (Details) - USD ($)		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Tax Expense related to a change in tax law		$ 0	$ 0	$ 466,000
Original Investment in Low Income Housing Projects		96,275,000	50,232,000	47,399,000
Amortization Method Qualified Affordable Housing Project Investments		72,510,000	33,681,000	35,225,000
Qualified Affordable Housing Project Investments, Commitment		34,967,000	3,935,000	4,536,000
Affordable Housing Tax Credits and Other Tax Benefits, Amount		7,342,000	5,407,000	5,654,000
Amortization Method Qualified Affordable Housing Project Investments, Amortization	[1]	5,645,000	4,377,000	4,402,000
Income (Loss) from Affordable Housing Projects, Equity Method Investments		$ 1,696,000	$ 1,030,000	1,253,000
Investments in Low Income Housing Projects [Member]
Tax Expense related to a change in tax law				$ 466,000
[1]	The 2017 amount is inclusive of $466,000 related to the revaluation of Low Income Housing tax credit investments as a result of the 2017 Tax Act.

EMPLOYEE BENEFIT PLANS (Details

EMPLOYEE BENEFIT PLANS (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Pension Plan [Member]
Multiemployer Plans [Line Items]
Multiemployer Plans, Funded Status [Fixed List]	At least 80 percent
FIP/RP Status Pending/Implemented	No
Surcharge Imposed	No
Expiration Date of Collective-Bargaining Agreement	N/A
Minimum Contributions Required for Future Periods	$ 0
Supplemental Executive Retirement Plans [Member]
Multiemployer Plans [Line Items]
Defined Benefit Plan, Benefit Obligation	17,361,000	$ 14,963,000	$ 15,749,000	$ 14,177,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	571,000
Contributions paid	486,000	$ 434,000	$ 367,000
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	$ 1,220,000

Pension Plan Contributions (Det

Pension Plan Contributions (Details) - Pension Plan [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Multiemployer Plans [Line Items]
Cash payment	$ 2,063	$ 2,642	$ 6,432
Multiemployer Plan Year Allocation Four [Member]
Multiemployer Plans [Line Items]
Cash payment		2,000	5,000
Multiemployer Plan Year Allocation One [Member]
Multiemployer Plans [Line Items]
Cash payment	$ 2,063
Multiemployer Plan Year Allocation Two [Member]
Multiemployer Plans [Line Items]
Cash payment		$ 642
Multiemployer Plan Year Allocation Three [Member]
Multiemployer Plans [Line Items]
Cash payment			$ 1,432

EMPLOYEE BENEFIT PLANS BHBK Pen

EMPLOYEE BENEFIT PLANS BHBK Pension Plan Benefits Table (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 18,300	$ 16,600
Other Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	11,653	9,697
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss)	1,886
Employer contribution	505
Defined Benefit Plan, Plan Assets, Benefits Paid	435
Defined Benefit Plan, Benefit Obligation	13,687	$ 10,824
Defined Benefit Plan, Interest Cost	424
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)	2,874
Defined Benefit Plan, Benefit Obligation, Benefits Paid	435
Defined Benefit Plan, Funded (Unfunded) Status of Plan	(2,034)
Defined Benefit Plan, Accumulated Benefit Obligation	$ 13,687

EMPLOYEE BENEFIT PLANS BHBK P_2

EMPLOYEE BENEFIT PLANS BHBK Pension Plan Net Periodic Pension Benefit Cost (Details) - Other Pension Plan [Member] $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Interest Cost	$ 424
Defined Benefit Plan, Expected Return (Loss) on Plan Assets	(780)
Defined Benefit Plan, Amortization of Gain (Loss)	327
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)	$ (29)

EMPLOYEE BENEFIT PLANS BHBK Sch

EMPLOYEE BENEFIT PLANS BHBK Schedule of Allocation of Plan Assets (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount		$ 18,300	$ 16,600
DefinedBenefitPlanFairValueofPlanAssetsExcludingNetAssetValueInvestments		5,726
DefinedBenefitPlanAlternativeInvestmentsFairValueOfPlanAssets	[1]	$ 5,927
Schedule of Allocation of Plan Assets [Table Text Block]		The fair value of major categories of the BHB Plan assets as of December 31, 2019 are summarized below: Fair Value Measurements at Reporting Date Using Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) (Dollars in thousands) Collective funds $ 967 967 $ — $ — Equity securities 1,131 1,131 — — Mutual funds 3,628 3,628 — — Total investments in the fair value hierarchy $ 5,726 $ 5,726 $ — $ — Investments measured at net asset value (1) 5,927 $ 11,653 (1) Under the Fair Value Measurements and Disclosure Topic of the FASB ASC, certain investments that were measured at fair value at net asset value per share (or its equivalent) have not been classified in the fair value hierarchy.
Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
DefinedBenefitPlanFairValueofPlanAssetsExcludingNetAssetValueInvestments		$ 5,726
Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
DefinedBenefitPlanFairValueofPlanAssetsExcludingNetAssetValueInvestments		0
Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
DefinedBenefitPlanFairValueofPlanAssetsExcludingNetAssetValueInvestments		0
Defined Benefit Plan, Common Collective Trust [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount		967
Defined Benefit Plan, Common Collective Trust [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount		967
Defined Benefit Plan, Common Collective Trust [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Defined Benefit Plan, Common Collective Trust [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Mutual Fund [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount		3,628
Mutual Fund [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount		3,628
Mutual Fund [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Mutual Fund [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Equity Securities [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount		1,131
Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount		1,131
Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Equity Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Other Pension Plan [Member]
Defined Benefit Plan, Plan Assets, Category [Line Items]
Defined Benefit Plan, Plan Assets, Amount		$ 11,653	$ 9,697
[1]	Under the Fair Value Measurements and Disclosure Topic of the FASB ASC, certain investments that were measured at fair value at net asset value per share (or its equivalent) have not been classified in the fair value hierarchy.

EMPLOYEE BENEFIT PLANS BHBK P_3

EMPLOYEE BENEFIT PLANS BHBK Pension Plan Expected Future Benefit Payments (Details) - Other Pension Plan [Member] $ in Thousands	Dec. 31, 2019USD ($)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	$ 629
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	834
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	591
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	583
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	556
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	$ 2,867

SERP Expense and Contributions

SERP Expense and Contributions paid (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Retirement expense	$ 1,400	$ 1,100	$ 1,900
Supplemental Employee Retirement Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Retirement expense	1,356	1,683	1,580
Contributions paid	$ 486	$ 434	$ 367

Expected future benefit payment

Expected future benefit payments under SERP (Details) - Supplemental Executive Retirement Plans [Member] $ in Thousands	Dec. 31, 2019USD ($)
Defined Benefit Plan Disclosure [Line Items]
2020	$ 472
2021	466
2022	458
2023	571
2024	1,220
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	$ 5,853

SERP Benefits Table (Details)

SERP Benefits Table (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Change in plan assets
Fair value of plan assets at beginning of year	$ 16,600
Fair value of plan assets at end of year	18,300	$ 16,600
Supplemental Executive Retirement Plans [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	14,963	15,749	$ 14,177
Service cost	433	459	423
Interest cost	601	533	547
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)	(1,850)	1,344	(969)
Accumulated benefit obligation at end of year	17,361	14,963	15,749
Defined Benefit Plan, Benefit Obligation, Benefits Paid	(486)	(434)	(367)
Change in plan assets
Employer contribution	486	434	367
Defined Benefit Plan, Plan Assets, Benefits Paid	(486)	(434)	(367)
Funded status at end of year	(17,361)	(14,963)	(15,749)
Assets for Plan Benefits, Defined Benefit Plan	0	0	0
Liabilities	(17,361)	(14,963)	(15,749)
Funded status at end of year	(17,361)	(14,963)	(15,749)
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax [Abstract]
Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), Gain (Loss), before Tax	3,509	1,705	3,465
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, Prior Service Cost (Credit), before Tax	494	770	1,047
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax	4,003	2,475	4,512
Information for plans with an accumulated benefit obligation in excess of plan assets
Projected benefit obligation	17,361	14,963	15,749
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Accumulated Benefit Obligation	17,361	14,963	15,749
Net periodic benefit cost
Service cost	433	459	423
Interest cost	601	533	547
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	276	276	276
Recognized net actuarial loss	46	415	334
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)	1,356	1,683	1,580
Defined Benefit Plan, Expected Amortization, Next Fiscal Year [Abstract]
Net actuarial loss	471	41	415
Net prior service cost	$ 276	$ 276	$ 276
Minimum [Member] | Supplemental Executive Retirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	2.00%	3.24%	2.48%
Defined Benefit Plan, Expected Amortization, Next Fiscal Year [Abstract]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	3.24%	2.48%	2.49%
Maximum [Member] | Supplemental Executive Retirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	3.04%	4.09%	3.45%
Defined Benefit Plan, Expected Amortization, Next Fiscal Year [Abstract]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	4.09%	3.45%	3.94%

EMPLOYEE BENEFIT PLANS (Detai_2

EMPLOYEE BENEFIT PLANS (Details Textual)	12 Months Ended
	Dec. 31, 2019USD ($)age	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)
Defined Contribution Plan Disclosure [Line Items]
Incentive plans and discretionary bonus expense	$ 16,300,000	$ 13,800,000	$ 10,900,000
Employer matching contribution percent	25.00%
Employee contribution percent	6.00%
Nondiscretionary requisite service period	1 year
Defined Contribution Plan, Nondiscretionary Requisite service hours	1,000
DefinedContributionPlanEmployerSafeHarborContributionAmount	3.00%
Nondiscretionary employer contribution, percent up to social security limit	2.00%
Nondiscretionary employer contribution, percent over social security limit	5.00%
Deferred Compensation Arrangement with Individual, Contributions by Employer	$ 142,000	142,000	143,000
Multiemployer Plans [Abstract]
Significance of contributions percentage	5.00%
Defined benefit plan expense	$ 1,400,000	1,100,000	1,900,000
Postretirement Benefits [Abstract]
Retirement age | age	65
Service period to be eligible for postretirement benefit	10 years
Death benefit	$ 5,000
Supplemental Executive Retirement Plans [Abstract]
Plan assets	18,300,000	16,600,000
401(k) Restoration Plan [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan expense	356,000	278,000	267,000
Employee Savings Plan [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan expense	6,600,000	5,400,000	5,000,000
Executive Vice President [Member]
Defined Contribution Plan Disclosure [Line Items]
Supplemental Unemployment Benefits, Salary Continuation	$ 295,000	287,000	$ 279,000
Other Pension Plan [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	4.03%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets	8.00%
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	3.11%
Supplemental Executive Retirement Plans [Abstract]
Plan assets	$ 11,653,000	$ 9,697,000
Equity Securities [Member]
Supplemental Executive Retirement Plans [Abstract]
Plan assets	$ 1,131,000
Minimum [Member] | Equity Securities [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	43.00%
Minimum [Member] | Fixed Income Securities [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	15.00%
Minimum [Member] | Other Investments [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	15.00%
Maximum [Member] | Equity Securities [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	57.00%
Maximum [Member] | Fixed Income Securities [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	25.00%
Maximum [Member] | Other Investments [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	31.00%

Recurring and Nonrecurring basi

Recurring and Nonrecurring basis (Details) - USD ($) $ in Thousands	Dec. 31, 2019		Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading	$ 2,200		$ 1,500
Equity Securities, FV-NI	21,261		19,477
Debt Securities, Available-for-sale	426,424		442,752
Assets
Total	76,705		26,113
Derivative Liability, Fair Value, Gross Liability	53,715		17,523
U.S. government agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	33,115		32,038
Agency mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	247,000		220,105
Pooled trust preferred securities issued by banks and insurers
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	1,114		1,329
Small Business Administration Pooled Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	54,795		51,927
Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading	2,179		1,504
Liabilities
Total recurring fair value measurements	507,633		478,951
Fair Value, Recurring [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI	21,261		19,477
Fair Value, Recurring [Member] | U.S. government agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	33,115		32,038
Fair Value, Recurring [Member] | Agency mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	247,000		220,105
Fair Value, Recurring [Member] | Agency collateralized mortgage obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	88,511		134,911
Fair Value, Recurring [Member] | State, county, and municipal securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	1,396		1,735
Fair Value, Recurring [Member] | Single issuer trust preferred securities issued by banks and insurers
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	493		707
Fair Value, Recurring [Member] | Pooled trust preferred securities issued by banks and insurers
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	1,114		1,329
Fair Value, Recurring [Member] | Small Business Administration Pooled Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	54,795		51,927
Fair Value, Recurring [Member] | Loans held for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Held-for-sale, Fair Value Disclosure	33,307		6,431
Fair Value, Recurring [Member] | Derivative instruments
Assets
Total	78,385		26,310
Fair Value, Recurring [Member] | Derivative instruments
Assets
Financial and Nonfinancial Liabilities, Fair Value Disclosure	53,923		17,523
Fair Value, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading	2,179		1,504
Liabilities
Total recurring fair value measurements	23,440		20,981
Fair Value, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI	21,261		19,477
Fair Value, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | State, county, and municipal securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale			0
Fair Value, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Small Business Administration Pooled Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	0		0
Fair Value, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Liabilities
Total recurring fair value measurements	483,079		456,641
Fair Value, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI	0		0
Fair Value, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | U.S. government agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	33,115		32,038
Fair Value, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Agency mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	247,000		220,105
Fair Value, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Agency collateralized mortgage obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	88,511		134,911
Fair Value, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | State, county, and municipal securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	1,396		1,735
Fair Value, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Single issuer trust preferred securities issued by banks and insurers
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	493		707
Fair Value, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Small Business Administration Pooled Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	54,795		51,927
Fair Value, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Loans held for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Held-for-sale, Fair Value Disclosure	33,307		6,431
Fair Value, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Derivative instruments
Assets
Total	78,385	[1]	26,310
Fair Value, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Derivative instruments
Assets
Financial and Nonfinancial Liabilities, Fair Value Disclosure			17,523
Fair Value, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Liabilities
Total recurring fair value measurements	1,114		1,329
Fair Value, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI	0		0
Fair Value, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | State, county, and municipal securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale			0
Fair Value, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Pooled trust preferred securities issued by banks and insurers
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	1,114		1,329
Fair Value, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Small Business Administration Pooled Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	0		0
Fair Value, Nonrecurring [Member]
Assets
Assets And Liabilities Fair Value Disclosure Nonrecurring	25,515		29,109
Fair Value, Nonrecurring [Member] | Collateral dependent impaired loans
Liabilities
Assets, Fair Value Disclosure	25,515		29,109
Fair Value, Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets
Assets And Liabilities Fair Value Disclosure Nonrecurring	25,515		29,109
Fair Value, Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Collateral dependent impaired loans
Liabilities
Assets, Fair Value Disclosure	$ 25,515		$ 29,109
[1]	All asset derivatives are located in other assets on the balance sheet

Level 3 Reconciliation (Details

Level 3 Reconciliation (Details) - Pooled Trust Preferred Securities [Member] - Fair Value, Inputs, Level 3 [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	$ 0	$ 0	$ 0
Reconciliation for all assets and liabilities measured at fair value on a recurring basis
Beginning balance	1,329	1,640	1,584
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases, (Sales), Issuances, (Settlements)	(189)	(502)	(21)
Sales	(26)	191	77
Ending Balance	$ 1,114	$ 1,329	$ 1,640

Unobservable Inputs (Details)

Unobservable Inputs (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Fair Value, Assets, Quantitative Information [Line Items]
Debt Securities, Available-for-sale	$ 426,424	$ 442,752
Weighted Average [Member] | Discounted cash flow methodology [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets, Quantitative Information [Line Items]
Cumulative Default	13.50%	16.20%
Loss Given Default	93.60%	94.80%
Cure Given Default	60.90%	60.90%
Pooled Trust Preferred Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets, Quantitative Information [Line Items]
Debt Securities, Available-for-sale	$ 1,114	$ 1,329
Pooled Trust Preferred Securities [Member] | Minimum [Member] | Discounted cash flow methodology [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets, Quantitative Information [Line Items]
Cumulative Default	2.00%	5.00%
Loss Given Default	85.00%	85.00%
Cure Given Default	0.00%	0.00%
Pooled Trust Preferred Securities [Member] | Maximum [Member] | Discounted cash flow methodology [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets, Quantitative Information [Line Items]
Cumulative Default	100.00%	100.00%
Loss Given Default	100.00%	100.00%
Cure Given Default	75.00%	75.00%
Fair Value, Recurring [Member] | Impaired Loans [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets, Quantitative Information [Line Items]
Assets, Fair Value Disclosure	$ 25,515	$ 29,109
Measurement Input, Constant Prepayment Rate [Member] | Weighted Average [Member] | Discounted cash flow methodology [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets, Quantitative Information [Line Items]
Debt Securities, Available-for-sale, Measurement Input	0.026	0.021
Measurement Input, Constant Prepayment Rate [Member] | Pooled Trust Preferred Securities [Member] | Minimum [Member] | Discounted cash flow methodology [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets, Quantitative Information [Line Items]
Debt Securities, Available-for-sale, Measurement Input	0	0
Measurement Input, Constant Prepayment Rate [Member] | Pooled Trust Preferred Securities [Member] | Maximum [Member] | Discounted cash flow methodology [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets, Quantitative Information [Line Items]
Debt Securities, Available-for-sale, Measurement Input	0.57	0.59

Fair value disclosure only tabl

Fair value disclosure only table (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Assets, Fair Value Disclosure [Abstract]
Debt Securities, Held-to-maturity	$ 740,806	$ 611,490
Loans and Leases Receivable, Net Amount	8,805,899	6,841,901
Securities held to maturity, fair value	753,263	603,640
Federal Home Loan Bank Stock	14,424	15,683
Bank Owned Life Insurance	197,372	160,456
Liabilities, Fair Value Disclosure [Abstract]
Advances from Federal Home Loan Banks	115,748	147,806
Junior subordinated debentures (less unamortized debt issuance costs of $40 and $118)	62,848	76,173
Subordinated Debt	49,601	34,728
Long-term Debt	74,906	0
Long-term Debt, Fair Value	72,219
Deposits [Member]
Liabilities, Fair Value Disclosure [Abstract]
Financial Liabilities Book Value	7,752,052	6,716,017
Accrued Liabilities, Fair Value Disclosure	7,752,052	6,716,017
Bank Time Deposits [Member]
Liabilities, Fair Value Disclosure [Abstract]
Financial Liabilities Book Value	1,395,315	711,103
Accrued Liabilities, Fair Value Disclosure	1,396,760	703,728
Federal Home Loan Bank Advances [Member]
Liabilities, Fair Value Disclosure [Abstract]
Advances from Federal Home Loan Banks	115,748	147,806
Federal Home Loan Bank Borrowings, Fair Value Disclosure	115,881	147,603
Junior Subordinated Debt [Member]
Liabilities, Fair Value Disclosure [Abstract]
Junior subordinated debentures (less unamortized debt issuance costs of $40 and $118)	62,848	76,173
Accrued Liabilities, Fair Value Disclosure	65,603	73,827
Subordinated Debt [Member]
Liabilities, Fair Value Disclosure [Abstract]
Subordinated Debt	49,601	34,728
Accrued Liabilities, Fair Value Disclosure	52,870	32,509
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Long-term Debt [Member]
Liabilities, Fair Value Disclosure [Abstract]
Long-term Debt, Fair Value	0
Significant Other Observable Inputs (Level 2) [Member] | Deposits [Member]
Liabilities, Fair Value Disclosure [Abstract]
Accrued Liabilities, Fair Value Disclosure	7,752,052	6,716,017
Significant Other Observable Inputs (Level 2) [Member] | Bank Time Deposits [Member]
Liabilities, Fair Value Disclosure [Abstract]
Accrued Liabilities, Fair Value Disclosure	1,396,760	703,728
Significant Other Observable Inputs (Level 2) [Member] | Federal Home Loan Bank Advances [Member]
Liabilities, Fair Value Disclosure [Abstract]
Federal Home Loan Bank Borrowings, Fair Value Disclosure	115,881
Accrued Liabilities, Fair Value Disclosure		147,603
Significant Other Observable Inputs (Level 2) [Member] | Junior Subordinated Debt [Member]
Liabilities, Fair Value Disclosure [Abstract]
Accrued Liabilities, Fair Value Disclosure	65,603	73,827
Significant Other Observable Inputs (Level 2) [Member] | Long-term Debt [Member]
Liabilities, Fair Value Disclosure [Abstract]
Long-term Debt, Fair Value	72,219
Significant Unobservable Inputs (Level 3) [Member] | Subordinated Debt [Member]
Liabilities, Fair Value Disclosure [Abstract]
Accrued Liabilities, Fair Value Disclosure	52,870	32,509
Significant Unobservable Inputs (Level 3) [Member] | Long-term Debt [Member]
Liabilities, Fair Value Disclosure [Abstract]
Long-term Debt, Fair Value	0
US Government Agencies Debt Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Debt Securities, Held-to-maturity	12,874
Securities held to maturity, fair value	12,997
US Government Agencies Debt Securities [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets, Fair Value Disclosure [Abstract]
Securities held to maturity, fair value	12,997
US Treasury Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Debt Securities, Held-to-maturity	4,032	1,004
Securities held to maturity, fair value	4,053	1,015
US Treasury Securities [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets, Fair Value Disclosure [Abstract]
Securities held to maturity, fair value	4,053	1,015
Agency mortgage-backed securities
Assets, Fair Value Disclosure [Abstract]
Debt Securities, Held-to-maturity	397,414	252,484
Securities held to maturity, fair value	405,802	250,928
Agency mortgage-backed securities | Significant Other Observable Inputs (Level 2) [Member]
Assets, Fair Value Disclosure [Abstract]
Securities held to maturity, fair value	405,802	250,928
Agency collateralized mortgage obligations
Assets, Fair Value Disclosure [Abstract]
Debt Securities, Held-to-maturity	293,662	332,775
Securities held to maturity, fair value	297,314	326,724
Agency collateralized mortgage obligations | Significant Other Observable Inputs (Level 2) [Member]
Assets, Fair Value Disclosure [Abstract]
Securities held to maturity, fair value	297,314	326,724
Single issuer trust preferred securities issued by banks and insurers
Assets, Fair Value Disclosure [Abstract]
Debt Securities, Held-to-maturity	1,500	1,500
Securities held to maturity, fair value	1,490	1,490
Single issuer trust preferred securities issued by banks and insurers | Significant Other Observable Inputs (Level 2) [Member]
Assets, Fair Value Disclosure [Abstract]
Securities held to maturity, fair value	1,490	1,490
Small Business Administration Pooled Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Debt Securities, Held-to-maturity	31,324	23,727
Securities held to maturity, fair value	31,607	23,483
Small Business Administration Pooled Securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets, Fair Value Disclosure [Abstract]
Securities held to maturity, fair value	0	0
Small Business Administration Pooled Securities [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets, Fair Value Disclosure [Abstract]
Securities held to maturity, fair value	31,607	23,483
Small Business Administration Pooled Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets, Fair Value Disclosure [Abstract]
Securities held to maturity, fair value	0	0
Loans Net Of Allowance For Loan Loses [Member]
Assets, Fair Value Disclosure [Abstract]
Loans and Leases Receivable, Net Amount	8,780,384	6,812,792
Loans, net of allowance for loan losses	8,613,635	6,635,209
Loans Net Of Allowance For Loan Loses [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets, Fair Value Disclosure [Abstract]
Loans, net of allowance for loan losses	8,613,635	6,635,209
Investment in Federal Home Loan Bank Stock [Member]
Assets, Fair Value Disclosure [Abstract]
Federal Home Loan Bank Stock	14,424	15,683
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure	14,424	15,683
Investment in Federal Home Loan Bank Stock [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets, Fair Value Disclosure [Abstract]
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure	0	0
Investment in Federal Home Loan Bank Stock [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets, Fair Value Disclosure [Abstract]
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure	14,424	15,683
Investment in Federal Home Loan Bank Stock [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets, Fair Value Disclosure [Abstract]
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure	0	0
Cash Surrender Value [Member]
Assets, Fair Value Disclosure [Abstract]
Bank Owned Life Insurance	197,372	160,456
Cash Surrender Value, Fair Value Disclosure	197,372	160,456
Cash Surrender Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets, Fair Value Disclosure [Abstract]
Cash Surrender Value, Fair Value Disclosure	0	0
Cash Surrender Value [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets, Fair Value Disclosure [Abstract]
Cash Surrender Value, Fair Value Disclosure	197,372	160,456
Cash Surrender Value [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets, Fair Value Disclosure [Abstract]
Cash Surrender Value, Fair Value Disclosure	$ 0	$ 0

REVENUE RECOGNITION (Details)

REVENUE RECOGNITION (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Other noninterest income - ASC 606									$ 8,696	$ 4,432	$ 4,569
Total noninterest income in scope of ASC 606									80,116	68,709	64,259
Total noninterest income out of scope of ASC 606									35,178	19,796	18,735
Noninterest Income	$ 33,297	$ 31,816	$ 28,648	$ 21,533	$ 23,491	$ 23,264	$ 21,887	$ 19,863	115,294	88,505	82,994
Deposit Account [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									20,040	18,327	17,822
Credit Card, Merchant Discount [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									18,262	15,433	13,899
ATM Charge [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									3,224	2,961	2,938
Investment Advisory, Management and Administrative Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									25,940	23,441	21,644
Investment Advisory, Retail Investment and Insurance Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									2,779	2,714	2,158
Merchant Processing [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									$ 1,175	$ 1,401	$ 1,229

REVENUE RECOGNITION CONTRACT WI

REVENUE RECOGNITION CONTRACT WITH CUSTOMER (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Contract with Customer, Asset and Liability [Abstract]
Investment Management Income Receivable	$ 2,341	$ 1,893

Reconciliation of changes in th

Reconciliation of changes in the components of OCI (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax				$ 180
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, after Tax		$ 12,017	$ 5,548	182
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax				(441)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, after Tax				(261)
Other Comprehensive Income (Loss), Available-for-sale Securities, Tax, Portion Attributable to Parent		(3,172)	1,422	322
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax		16,725	7,717	307
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, Tax		(4,708)	(2,169)	(125)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax		2,346	1,000	(441)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax		660	281
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, after Tax		1,686	719
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, before Tax		14,379	6,717
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, Tax		4,048	1,888
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax		10,331	4,829	443
Other Comprehensive Income (Loss), before Tax [Abstract]
Change in fair value of securities available for sale, pre tax amount		(12,055)	5,923	996
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax, Portion Attributable to Parent				748
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, before Tax		(2,123)	1,521	(995)
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax		(8)	372	278
Amortization of certain costs included in net periodic retirement costs, pre tax amount		(276)	(276)	(276)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax	[1]	(1,855)	2,169	(441)
Total other comprehensive loss, pre tax amount		26,041	2,963	(692)
Other Comprehensive Income (Loss), Tax [Abstract]
Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, Tax		(2,761)	1,422	321
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax, Portion Attributable to Parent				(305)
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, Tax		597	(428)	407
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, Tax		2	(105)	(113)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, Tax		(78)	(78)	(113)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax	[1]	521	(611)	181
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent		(6,699)	(1,077)	198
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, after Tax		9,294	(4,501)	(675)
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Portion Attributable to Parent		10,345	(4,501)	(677)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Portion Attributable to Parent				443
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, after Tax		(1,526)	1,093	(588)
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, after Tax		(6)	267	165
Amortization of certain costs included in net periodic retirement costs, after tax amount		198	198	163
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	[1]	(1,334)	1,558	(260)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent		19,342	1,886	(494)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax		(1,462)	0	3
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax		411	0	(1)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax		(1,051)	0	2
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax, Portion Attributable to Parent		$ 13,517	$ (5,923)	$ (999)
[1]	The amortization of prior service costs is included in the computation of net periodic pension costs as disclosed in Note 15 - Employee Benefit Plans .

Accumlated other comprehensive

Accumlated other comprehensive income table (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017		Sep. 30, 2018	[3]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Prior Period Reclassification Adjustment	[1]		$ 0
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets				$ 177	[2]	$ 0
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance		$ (1,173)	(1,831)	(1,337)
Total other comprehensive income (loss)		19,342	1,886	(494)
Ending Balance		18,169	(1,173)	(1,831)
Unrealized Gain (Loss) on Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Prior Period Reclassification Adjustment			(111)
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets			(831)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance		(5,947)	(504)	173
Total other comprehensive income (loss)		10,345	(4,501)	(677)
Ending Balance		4,398	(5,947)	(504)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Prior Period Reclassification Adjustment			205
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets			0
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance		6,148	948
Total other comprehensive income (loss)		10,331
Ending Balance			6,148	948
Unrealized Gain (Loss) on Cash Flow Hedge
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance				361
Total other comprehensive income (loss)			4,995	587
Ending Balance		16,479
Deferred Gain on Hedge Transactions
Accumulated Other Comprehensive Income (Loss) [Line Items]
Prior Period Reclassification Adjustment			29
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets			0
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance		0	137	281
Total other comprehensive income (loss)		0	(166)	(144)
Ending Balance		0	0	137
Defined Benefit Postretirement Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Prior Period Reclassification Adjustment			(520)
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets			0
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance		(1,374)	(2,412)	(2,152)
Total other comprehensive income (loss)		(1,334)	1,558	(260)
Ending Balance		(2,708)	(1,374)	(2,412)
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Prior Period Reclassification Adjustment	[1]		(397)
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets	[3]		(831)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Total other comprehensive income (loss)		$ 19,342	$ 1,886	$ (494)
[1]	Represents adjustment needed to reflect the cumulative impact on retained earnings for reclassification of the income tax effects attributable to accumulated other comprehensive income, as a result of the Tax Cuts and Jobs Act (the "Tax Act"). Pursuant to the Company's adoption of Accounting Standards Update 2018-02, the Company has elected to reclassify amounts stranded in other comprehensive income to retained earnings.
[2]	Represents adjustment needed to reflect the cumulative impact on retained earnings for previously recognized stock based compensation, which included an adjustment for estimated forfeitures. Pursuant to the Company's adoption of Accounting Standards Update 2016-09, the Company has elected to recognize stock based compensation without inclusion of a forfeiture estimate, and as such has recognized this adjustment to present retained earnings consistent with this election.
[3]	Represents adjustment needed to reflect the cumulative impact on retained earnings for the classification and measurement of investments in equity securities. Pursuant to the Company's adoption of Accounting Standards Update 2016-01, the Company's investments in equity securities will no longer be classified as available for sale, therefore the Company was required to reclassify the net unrealized gain recognized on the change in fair value of these equity securities from other comprehensive income to retained earnings.

OTHER COMPREHENSIVE LOSS (Detai

OTHER COMPREHENSIVE LOSS (Details Textual) - USD ($)	Dec. 31, 2017	Dec. 31, 2009
Equity [Abstract]
Gain on interest rate swaps	$ 137,000	$ 1,400,000

LEASES (Details)

LEASES (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Leases [Abstract]
Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months	$ 11,752,000
Operating Lease, Cost	10,718,000
Short-term Lease, Cost	116,000
Variable Lease, Cost	0
Lease, Cost	10,834,000
Lessee, Operating Lease, Liability, Payments, Due Year Two	11,052,000
Lessee, Operating Lease, Liability, Payments, Due Year Three	10,438,000
Lessee, Operating Lease, Liability, Payments, Due Year Four	8,528,000
Lessee, Operating Lease, Liability, Payments, Due Year Five	7,121,000
Lessee, Operating Lease, Liability, Payments, Due after Year Five	14,900,000
Lessee, Operating Lease, Liability, Payments, Due	63,791,000
Operating Lease, Liability, Undiscounted Excess Amount	5,489,000
Operating Lease, Liability	$ 58,302,000	$ 34,100,000	$ 0

LEASES Textual (Details)

LEASES Textual (Details) $ in Millions	Dec. 31, 2019USD ($)	Jan. 01, 2019USD ($)
Lessee, Lease, Description [Line Items]
Operating Lease, Weighted Average Remaining Lease Term	6 years 5 months 4 days
Operating Lease, Weighted Average Discount Rate, Percent	2.75%
Operating Lease, Right-of-Use Asset	$ 56.6	$ 32.8
Property Subject to or Available for Operating Lease, Number of Units	94
Maximum [Member]
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease, Renewal Term	10 years
Minimum [Member]
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease, Renewal Term	1 year

COMMITMENTS AND CONTINGENCIES F

COMMITMENTS AND CONTINGENCIES Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Commitments to Extend Credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet financial instruments	$ 3,337,930	$ 2,639,689
Standby letters of credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet financial instruments	21,565	16,708
Deferred standby letter of credit fees [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet financial instruments	158	$ 122
Obligation to Repurchase Receivables Sold [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet financial instruments	$ 404,532

COMMITMENTS AND CONTINGENCIES_2

COMMITMENTS AND CONTINGENCIES (Details Textual) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Guarnator Obligations [Line Items]
Reserve requirement	$ 0	$ 53.5

REGULATORY CAPITAL REQUIREMEN_3

REGULATORY CAPITAL REQUIREMENTS (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Company (consolidated) [Member]
Total capital (to risk weighted assets):
Actual	$ 1,352,341	$ 992,454
Actual Ratio	14.83%	14.45%
Capital Required for Capital Adequacy	$ 729,291	$ 549,297
For Capital Adequacy Purposes Ratio	8.00%	8.00%
Common Equity Tier One Capital	$ 1,171,963	$ 818,176
Common Equity tier One Capital to Risk Weighted Assets	12.86%	11.92%
Common Equity Tier One Capital Required for Capital Adequacy	$ 410,226	$ 308,980
Common Equity Tier One Capital for Capitalized Adequacy to Risk Weighted Assets	4.50%	4.50%
Tier 1 capital (to risk weighted assets):
Actual	$ 1,232,963	$ 892,176
Actual Ratio	13.53%	12.99%
For Capital Adequacy Purposes	$ 546,969	$ 411,973
For Capital Adequacy Purposes Ratio	6.00%	6.00%
Tier 1 capital (to average assets):
Actual	$ 1,232,963	$ 892,176
Actual Ratio	11.28%	10.69%
For Capital Adequacy Purposes	$ 437,271	$ 333,754
For Capital Adequacy Purposes Ratio	4.00%	4.00%
Bank [Member]
Total capital (to risk weighted assets):
Actual	$ 1,275,611	$ 937,574
Actual Ratio	14.00%	13.66%
Capital Required for Capital Adequacy	$ 728,868	$ 549,036
For Capital Adequacy Purposes Ratio	8.00%	8.00%
To Be Well Capitalized Under Prompt Corrective Action Provisions	$ 911,085	$ 686,295
To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	10.00%	10.00%
Common Equity Tier One Capital	$ 1,205,740	$ 872,024
Common Equity tier One Capital to Risk Weighted Assets	13.23%	12.71%
Common Equity Tier One Capital Required for Capital Adequacy	$ 409,988	$ 308,833
Common Equity Tier One Capital for Capitalized Adequacy to Risk Weighted Assets	4.50%	4.50%
Common Equity Tier 1 Capital to be Well Capitalized	$ 592,205	$ 446,092
Common Equity Tier One Capital to be Well Capitalized to Risk Weighted Assets	6.50%	6.50%
Tier 1 capital (to risk weighted assets):
Actual	$ 1,205,740	$ 872,024
Actual Ratio	13.23%	12.71%
For Capital Adequacy Purposes	$ 546,651	$ 411,777
For Capital Adequacy Purposes Ratio	6.00%	6.00%
To Be Well Capitalized Under Prompt Corrective Action Provisions	$ 728,868	$ 549,036
To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	8.00%	8.00%
Tier 1 capital (to average assets):
Actual	$ 1,205,740	$ 872,024
Actual Ratio	11.06%	10.46%
For Capital Adequacy Purposes	$ 435,886	$ 333,595
For Capital Adequacy Purposes Ratio	4.00%	4.00%
To Be Well Capitalized Under Prompt Correction Action Provisions	$ 544,857	$ 416,994
To Be Well Capitalized Under Prompt Correction Action Provisions Ratio	5.00%	5.00%

REGULATORY CAPITAL REQUIREMEN_4

REGULATORY CAPITAL REQUIREMENTS Regulatory Capital Requirements (Details Textual) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Redemption of Trust Preferred Securities	$ 13
Dividends received from subsidiaries	181.7	$ 71.2
Junior Subordinated Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 61	$ 74

Parent Company Balance Sheet (D

Parent Company Balance Sheet (Details) - USD ($)		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Assets:
Deferred tax asset		$ 61,423,000	$ 39,494,000
Derivative Asset		76,705,000	26,113,000
Other Assets		343,353,000	132,507,000
Total assets		11,395,165,000	8,851,592,000
Liabilities and stockholders’ equity
Long-term Debt		74,906,000	0
Junior subordinated debentures (less unamortized debt issuance costs of $40 and $118)		62,848,000	76,173,000
Subordinated debentures (less unamortized debt issuance costs of $399 and $272)		49,601,000	34,728,000
Other liabilities		236,552,000	92,275,000
Total liabilities		9,687,022,000	7,778,102,000
Stockholders’ equity		1,708,143,000	1,073,490,000	$ 943,809,000	$ 864,690,000
Liabilities and Equity		11,395,165,000	8,851,592,000
Parent Company [Member]
Assets:
Cash	[1]	135,688,000	64,256,000
Investments in subsidiaries	[2]	1,743,435,000	1,128,407,000
Prepaid income taxes		31,586,000	1,014,000
Deferred tax asset		612,000
Derivative Asset	[1]	290,000	1,711,000
Other Assets		0	37,000
Total assets		1,911,611,000	1,195,425,000
Liabilities and stockholders’ equity
Dividends payable		15,126,000	10,671,000
Long-term Debt		74,906,000	0
Junior subordinated debentures (less unamortized debt issuance costs of $40 and $118)		62,848,000	76,173,000
Subordinated debentures (less unamortized debt issuance costs of $399 and $272)		49,601,000	34,728,000
Other liabilities		987,000	363,000
Total liabilities		203,468,000	121,935,000
Stockholders’ equity		1,708,143,000	1,073,490,000
Liabilities and Equity		1,911,611,000	1,195,425,000
Junior Subordinated Debt [Member]
Liabilities and stockholders’ equity
Unamortized Debt Issuance Expense		40,000	118,000
Junior Subordinated Debt [Member] | Parent Company [Member]
Liabilities and stockholders’ equity
Unamortized Debt Issuance Expense		40,000	118,000
Long-term Debt [Member]
Liabilities and stockholders’ equity
Unamortized Debt Issuance Expense		94,000	0
Long-term Debt [Member] | Parent Company [Member]
Liabilities and stockholders’ equity
Unamortized Debt Issuance Expense		94,000	0
Subordinated Debt [Member]
Liabilities and stockholders’ equity
Unamortized Debt Issuance Expense		399,000	272,000
Subordinated Debt [Member] | Parent Company [Member]
Liabilities and stockholders’ equity
Unamortized Debt Issuance Expense		$ 399,000	$ 272,000
[1]	Entire balance eliminates in consolidation.
[2]	Majority of balance eliminates in consolidation

Parent Company Income Statement

Parent Company Income Statement (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Expenses
Interest expense		$ 13,710	$ 15,026	$ 16,125	$ 9,018	$ 7,618	$ 6,641	$ 5,999	$ 5,278	$ 53,879	$ 25,536	$ 18,334
Income tax benefit		14,368	17,036	10,007	11,522	8,258	9,969	9,249	6,828	52,933	34,304	47,341
Net Income		$ 47,477	$ 51,845	$ 30,628	$ 35,225	$ 29,934	$ 33,015	$ 31,118	$ 27,555	165,175	121,622	87,204
Parent Company [Member]
Income
Dividend Income, Operating	[1]									181,790	71,255	47,006
Interest income (2)	[2]											50
Total income										181,790	71,255	47,056
Expenses
Interest expense										8,236	4,234	3,995
Total expenses										8,236	4,234	3,995
Income before income taxes and equity in undistributed income of subsidiaries										173,554	67,021	43,061
Income tax benefit										(2,262)	(1,151)	(1,523)
Income of parent company										175,816	68,172	44,584
Equity (deficit) in undistributed income of subsidiaries										(10,641)	53,450	42,620
Net Income										$ 165,175	$ 121,622	$ 87,204
[1]	Majority of balance eliminates in consolidation.
[2]	Entire balance eliminated in consolidation.

Parent Company Cash Flow Statem

Parent Company Cash Flow Statement (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Condensed Financial Statements, Captions [Line Items]
Net income		$ 47,477	$ 51,845	$ 30,628	$ 35,225	$ 29,934	$ 33,015	$ 31,118	$ 27,555	$ 165,175	$ 121,622	$ 87,204
Adjustments to reconcile net income to net cash provided by operating activities
Deferred income tax expense										10,594	(4,497)	9,211
Change in other liabilities										19,283	7,100	(3,825)
Net cash provided by operating activities										216,522	141,837	130,909
Cash flows provided by (used) in investing activities
Net cash used in investing activities										20,160	(387,511)	(316,769)
Cash flows provided by (used in) financing activities
Proceeds from Lines of Credit										49,980	0	0
Repayments of Lines of Credit										(49,980)	0	0
Proceeds from Debt, Net of Issuance Costs										74,867	0	0
Proceeds from Issuance of Subordinated Long-term Debt										49,526	0	0
Repayments of Subordinated Debt										34,767	0	0
Restricted stock awards issued, net of awards surrendered										(1,463)	(1,371)	(1,422)
Cash received from stock option exercises										281	184	214
Proceeds from shares issued under the direct stock purchase plan										4,951	2,712	1,636
Common dividends paid										(53,274)	(40,167)	(34,045)
Net cash provided by financing activities										(336,163)	283,013	109,881
Net increase (decrease) in cash and cash equivalents										(99,481)	37,339	(75,979)
Cash and cash equivalents at beginning of year					250,455				213,116	250,455	213,116	289,095
Cash and cash equivalents at end of period		150,974				250,455				150,974	250,455	213,116
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Investments in subsidiaries	[1]	1,743,435				1,128,407				1,743,435	1,128,407
Net income										165,175	121,622	87,204
Adjustments to reconcile net income to net cash provided by operating activities
Amortization										157	54	12
Deferred income tax expense										1,021	49	51
Change in prepaid income taxes and other assets										20,556	135	(99)
Change in other liabilities										(4,613)	6	(562)
Deficit (equity) in undistributed income of subsidiaries										10,641	(53,450)	(42,620)
Net cash provided by operating activities										192,937	68,416	43,986
Cash flows provided by (used) in investing activities
Cash paid for acquisitions, net of cash acquired (1)	[2]									(148,297)	(13,649)	(4,834)
Net cash used in investing activities										(148,297)	(13,649)	(4,834)
Cash flows provided by (used in) financing activities
Proceeds from Lines of Credit										49,980	0	0
Repayments of Lines of Credit										(49,980)	0	0
Proceeds from Debt, Net of Issuance Costs										74,867	0	0
Proceeds from Issuance of Subordinated Long-term Debt										49,526	0	0
Restricted stock awards issued, net of awards surrendered										(1,463)	(1,371)	(1,422)
Cash received from stock option exercises										281	184	214
Proceeds from shares issued under the direct stock purchase plan										4,951	2,712	1,636
Common dividends paid										(53,274)	(40,167)	(34,045)
Net cash provided by financing activities										26,792	(38,642)	(33,617)
Net increase (decrease) in cash and cash equivalents										71,432	16,125	5,535
Cash and cash equivalents at beginning of year					$ 64,256				$ 48,131	64,256	48,131	42,596
Cash and cash equivalents at end of period		135,688				64,256				135,688	64,256	48,131
Cash	[3]	$ 135,688				$ 64,256				135,688	64,256
Junior Subordinated Debt [Member] | Parent Company [Member]
Cash flows provided by (used in) financing activities
Repayments of Subordinated Debt										(13,329)	0	0
Subordinated Debt [Member] | Parent Company [Member]
Cash flows provided by (used in) financing activities
Repayments of Subordinated Debt										$ (34,767)	$ 0	$ 0
[1]	Majority of balance eliminates in consolidation
[2]	The majority of the net assets acquired at the parent company represented each of the acquired companies' investments in their wholly owned subsidiaries, which were eliminated in consolidation at December 31, 2019 , 2018 , and 2017 , respectively.
[3]	Entire balance eliminates in consolidation.

SELECTED QUARTERLY FINANCIAL _3

SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Interest income	$ 113,703	$ 119,624	$ 122,144	$ 91,543	$ 87,910	$ 82,875	$ 79,167	$ 73,749	$ 447,014	$ 323,701	$ 277,194
Interest expense	13,710	15,026	16,125	9,018	7,618	6,641	5,999	5,278	53,879	25,536	18,334
Net interest income	99,993	104,598	106,019	82,525	80,292	76,234	73,168	68,471	393,135	298,165	258,860
Provision (benefit)	4,000	0	1,000	1,000	1,200	1,075	2,000	500	6,000	4,775	2,950
Total noninterest income	33,297	31,816	28,648	21,533	23,491	23,264	21,887	19,863	115,294	88,505	82,994
Total noninterest expenses	67,445	67,533	93,032	56,311	64,391	55,439	52,688	53,451	284,321	225,969	204,359
Provision for income taxes	14,368	17,036	10,007	11,522	8,258	9,969	9,249	6,828	52,933	34,304	47,341
Net Income	$ 47,477	$ 51,845	$ 30,628	$ 35,225	$ 29,934	$ 33,015	$ 31,118	$ 27,555	$ 165,175	$ 121,622	$ 87,204
Basic earnings per share (in dollars per share)	$ 1.38	$ 1.51	$ 0.89	$ 1.25	$ 1.08	$ 1.20	$ 1.13	$ 1	$ 5.03	$ 4.41	$ 3.19
Diluted earnings per share (in dollars per share)	$ 1.38	$ 1.51	$ 0.89	$ 1.25	$ 1.07	$ 1.20	$ 1.13	$ 1	$ 5.03	$ 4.40	$ 3.19
Weighted average common shares (basic) (in shares)	34,374,953	34,361,176	34,313,492	28,106,184	27,815,437	27,537,841	27,526,653	27,486,573	32,810,433	27,592,380	27,294,028
Common share equivalents (in shares)	46,245	39,390	41,878	54,466	58,576	63,499	54,525	67,381	45,801	61,428	78,076
Weighted average common shares (diluted) (in shares)	34,421,198	34,400,566	34,355,370	28,160,650	27,874,013	27,601,340	27,581,178	27,553,954	32,856,234	27,653,808	27,372,104
Gain (Loss) on Sales of Loans, Net		$ 951							$ 13,200	$ 3,600	$ 4,700
Total Unusual or infrequent Income Items	$ 0	951	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0
Acquisition Related Costs	0	705	24,696	1,032	8,046	2,688	434	0	$ 26,433	$ 11,168	$ 3,393
Adjustment for tax effect of previously incurred M&A expense				650
Total unusual or infrequent expense items	$ 0	$ 705	$ 24,696	$ 1,682	$ 8,046	$ 2,688	$ 434	$ 0

TRANSACTIONS WITH RELATED PAR_3

TRANSACTIONS WITH RELATED PARTIES (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Loans and Leases Receivable, Related Parties		$ 55,830	$ 41,170	$ 52,458
Loans and Leases Receivable, Related Parties, Additions	[1]	49,771	14,862
Loans and Leases Receivable, Related Parties, Collections		(35,111)	(14,057)
Loans and Leases Receivable, Related Parties, Period Increase (Decrease)		$ 0	$ (12,093)
[1]	The 2019 amount includes $7.0 million of BHB acquired loans associated with a director during the year, which represent the outstanding loan balances at the effective date of appointment.

TRANSACTIONS WITH RELATED PAR_4

TRANSACTIONS WITH RELATED PARTIES Related Parties Textual (Details) - USD ($)		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Nonaccrual/TDR Loans, with related parties		$ 0	$ 0
Loans and Leases Receivable, Related Parties, Additions	[1]	0	0
Related Party Transaction, Amounts of Transaction		7,000,000
Related Party Deposit Liabilities		$ 13,000,000	$ 10,800,000
[1]	The 2019 amount includes $7.0 million of BHB acquired loans associated with a director during the year, which represent the outstanding loan balances at the effective date of appointment.

Uncategorized Items - indb12-31

Label	Element	Value
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities	$ 2,106,110,000
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	32,777,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets	$ 2,711,067,000
Long-term Debt [Member] | Long-term Debt [Member]
Debt Instrument, Interest Rate, Stated Percentage	us-gaap_DebtInstrumentInterestRateStatedPercentage	3.19%
Long-term Debt [Member] | Long-term Debt [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1	1.25%
Subordinated note due 2029 [Member] | Subordinated Debt [Member]
Subordinated Debt	us-gaap_SubordinatedDebt	$ 50,000,000