The amount of identifiable net tangible assets acquired at the acquisition date.

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Refers to the factor of straight-line rate of depreciation used in declining balance depreciation method.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an investments acquired in a business combination.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of loans acquired in a business combination.

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Refers to the number of branch locations added upon merger.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of property, plant and equipment acquired in a business combination.

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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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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 assets acquired at the acquisition date.

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- Definition

Amount of deferred tax liability attributable to taxable temporary differences assumed at the acquisition date.

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Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the 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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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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No definition available.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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ACQUISITIONS (Details) shares in Thousands, $ in Millions			3 Months Ended		9 Months Ended
ACQUISITIONS (Details) shares in Thousands, $ in Millions	May 12, 2017 USD ($) Branch Location shares	Feb. 03, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Sep. 30, 2017 USD ($)
Business Acquisition [Line Items]
Increase (decrease) in other assets as a result of reclassification and adjustment			$ 5.5	$ (2.7)
Increase (decrease) in other liabilities as a result of reclassification and adjustment			6.6	(2.4)
Increase in investments as a result of updated information not available at the time of acquisition			0.2
Decrease in loans as a result of an adjustment to the valuation of acquired impaired loans			(0.6)
Increase in premises and equipment as a result of updated appraisal information not available at the time of acquisition			3.6
Merchants Bancshares, Inc. [Member]
Business Acquisition [Line Items]
Issuance of common shares (in shares) \| shares	4,680
Assets acquired	$ 1,990.0
Revenues earned			16.8		$ 25.8
Expenses incurred			7.5		11.5
Increase (decrease) in goodwill as a result of fair value adjustment			(2.0)
Merchants Bancshares, Inc. [Member] \| VERMONT [Member]
Business Acquisition [Line Items]
Number of branch locations added upon merger \| Branch	31
Merchants Bancshares, Inc. [Member] \| MASSACHUSETTS [Member]
Business Acquisition [Line Items]
Number of branch locations added upon merger \| Location	1
Northeast Retirement Services, Inc. [Member]
Business Acquisition [Line Items]
Tangible assets, net		$ 36.1
Factor of straight-line rate of depreciation used in declining balance depreciation method		150.00%
Period of amortization		10 years
Deferred tax liability		$ 24.2
Revenues earned			8.7		22.1
Expenses incurred			5.8		$ 15.1
Increase (decrease) in goodwill as a result of fair value adjustment			$ (0.1)	$ 0.3