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ACQUISITIONS, Intangible Asset, Goodwill and Acquisition-related Expenses (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Summary of loans acquired [Abstract] |  |  |  |
Merger and acquisition integration-related expenses | $ 71 | $ 22,896 | $ 63 | $ 24,612
HR Consultants (SA), LLC [Member] | Core Deposits [Member] |  |  |  |
Intangible Assets [Abstract] |  |  |  |
Estimated useful life |  |  | 8 years |
HR Consultants (SA), LLC [Member] | Other Intangibles [Member] |  |  |  |
Intangible Assets [Abstract] |  |  |  |
Estimated useful life |  |  | 8 years |
Penna & Associates Agency, Inc. [Member] | Core Deposits [Member] |  |  |  |
Intangible Assets [Abstract] |  |  |  |
Estimated useful life |  |  | 8 years |
Penna & Associates Agency, Inc. [Member] | Other Intangibles [Member] |  |  |  |
Intangible Assets [Abstract] |  |  |  |
Estimated useful life |  |  | 8 years |
Styles Bridges Associates [Member] | Core Deposits [Member] |  |  |  |
Intangible Assets [Abstract] |  |  |  |
Estimated useful life |  |  | 8 years |
Styles Bridges Associates [Member] | Other Intangibles [Member] |  |  |  |
Intangible Assets [Abstract] |  |  |  |
Estimated useful life |  |  | 8 years |
Gordon B. Roberts Agency, Inc [Member] | Core Deposits [Member] |  |  |  |
Intangible Assets [Abstract] |  |  |  |
Estimated useful life |  |  | 8 years |
Gordon B. Roberts Agency, Inc [Member] | Other Intangibles [Member] |  |  |  |
Intangible Assets [Abstract] |  |  |  |
Estimated useful life |  |  | 8 years |
Northeast Capital Management, Inc [Member] | Core Deposits [Member] |  |  |  |
Intangible Assets [Abstract] |  |  |  |
Estimated useful life |  |  | 8 years |
Northeast Capital Management, Inc [Member] | Other Intangibles [Member] |  |  |  |
Intangible Assets [Abstract] |  |  |  |
Estimated useful life |  |  | 8 years |
Merchants Bancshares, Inc. [Member] | Core Deposits [Member] |  |  |  |
Intangible Assets [Abstract] |  |  |  |
Estimated useful life |  |  | 8 years |
Merchants Bancshares, Inc. [Member] | Other Intangibles [Member] |  |  |  |
Intangible Assets [Abstract] |  |  |  |
Estimated useful life |  |  | 8 years |
Dryfoos Insurance Agency, Inc [Member] | Core Deposits [Member] |  |  |  |
Intangible Assets [Abstract] |  |  |  |
Estimated useful life |  |  | 8 years |
Dryfoos Insurance Agency, Inc [Member] | Other Intangibles [Member] |  |  |  |
Intangible Assets [Abstract] |  |  |  |
Estimated useful life |  |  | 8 years |
Benefits Advisory Service, Inc [Member] | Core Deposits [Member] |  |  |  |
Intangible Assets [Abstract] |  |  |  |
Estimated useful life |  |  | 8 years |
Benefits Advisory Service, Inc [Member] | Other Intangibles [Member] |  |  |  |
Intangible Assets [Abstract] |  |  |  |
Estimated useful life |  |  | 8 years |

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- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460 + Details
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- Definition Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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