Amount of deposits acquired in an acquisition.

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Refers to the number of branch locations to be added upon merger.

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The expected number of new branch locations upon completion of the merger, as a result of the acquisition or purchase agreement.

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Amount of addition (reduction) to the amount at which an asset could be incurred (settled) in a current transaction between willing parties.

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Number of shares of equity interests issued or issuable to acquire entity.

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-Name Accounting Standards Codification
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-SubTopic 30
-Section 50
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of assets acquired at the acquisition date.

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Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of addition (reduction) to the amount at which a liability could be incurred (settled) in a current transaction between willing parties.

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No definition available.

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ACQUISITIONS (Details) shares in Thousands, $ in Thousands			3 Months Ended	9 Months Ended
ACQUISITIONS (Details) shares in Thousands, $ in Thousands	Oct. 24, 2016 USD ($) Location Branch	Dec. 04, 2015 USD ($) Branch shares	Mar. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)
Business Acquisition [Line Items]
Increase in goodwill as a result of fair value adjustment				$ 1,890
Merchants Bancshares, Inc. [Member] \| Subsequent Event [Member]
Business Acquisition [Line Items]
Purchase price of acquisition	$ 304,000
Deposits to be acquired	1,500,000
Assets acquired	$ 1,900,000
Merchants Bancshares, Inc. [Member] \| Subsequent Event [Member] \| VERMONT [Member]
Business Acquisition [Line Items]
Number of branch locations to be added upon merger \| Branch	31
Merchants Bancshares, Inc. [Member] \| Subsequent Event [Member] \| MASSACHUSETTS [Member]
Business Acquisition [Line Items]
Number of branch locations to be added upon merger \| Location	1
Oneida Financial Corp [Member]
Business Acquisition [Line Items]
Deposits to be acquired		$ 699,241
Issuance of common shares (in shares) \| shares		2,380
Number of new branch locations included in acquisition or purchase agreement \| Branch		12
Assets acquired		$ 769,000
Decrease in other assets as a result of fair value adjustment			$ (900)
Increase in other liabilities as a result of fair value adjustment			700
Increase in goodwill as a result of fair value adjustment			$ 1,600