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ACQUISITIONS (Details) shares in Thousands, $ in Millions |  |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | --- | ---
May 12, 2017 USD ($) Branch Location shares | Feb. 03, 2017 USD ($) | Jun. 30, 2017 USD ($) | Jun. 30, 2017 USD ($)
Merchants Bancshares, Inc. [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Issuance of common shares (in shares) | shares | 4,680 |  |  |
Assets acquired | $ 1,990.0 |  |  |
Revenues earned |  |  | $ 8.9 | $ 8.9
Expenses incurred |  |  | 4.0 | 4.0
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 |  | $ 36.0 |  |
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 |  |  | 8.4 | 13.4
Expenses incurred |  |  | 5.7 | $ 9.3
Decrease in other assets as a result of reclassification and adjustment |  |  | (2.7) |
Decrease in other liabilities as a result of reclassification and adjustment |  |  | (2.4) |
Increase in goodwill as a result of fair value adjustment |  |  | $ 0.3 |

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