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ACQUISITIONS, Summary of Loans Acquired (Details) - USD ($) $ in Thousands | Jul. 12, 2019 | May 12, 2017
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Kinderhook Bank Corp [Member] |  |
Summary of loans acquired [Abstract] |  |
Contractually required principal and interest at acquisition | $ 649,734 |
Contractual cash flows not expected to be collected | (9,648) |
Expected cash flows at acquisition | 640,086 |
Interest component of expected cash flows | (160,209) |
Fair value of acquired loans | 479,877 |
Kinderhook Bank Corp [Member] | Acquired Impaired Loans [Member] |  |
Summary of loans acquired [Abstract] |  |
Contractually required principal and interest at acquisition | 13,350 |
Contractual cash flows not expected to be collected | (4,176) |
Expected cash flows at acquisition | 9,174 |
Interest component of expected cash flows | (551) |
Fair value of acquired loans | 8,623 |
Kinderhook Bank Corp [Member] | Acquired Non Impaired Loans [Member] |  |
Summary of loans acquired [Abstract] |  |
Contractually required principal and interest at acquisition | 636,384 |
Contractual cash flows not expected to be collected | (5,472) |
Expected cash flows at acquisition | 630,912 |
Interest component of expected cash flows | (159,658) |
Fair value of acquired loans | $ 471,254 |
Merchants Bancshares, Inc. [Member] |  |
Summary of loans acquired [Abstract] |  |
Contractually required principal and interest at acquisition |  | $ 1,888,028
Contractual cash flows not expected to be collected |  | (20,138)
Expected cash flows at acquisition |  | 1,867,890
Interest component of expected cash flows |  | (379,733)
Fair value of acquired loans |  | 1,488,157
Merchants Bancshares, Inc. [Member] | Acquired Impaired Loans [Member] |  |
Summary of loans acquired [Abstract] |  |
Contractually required principal and interest at acquisition |  | 15,454
Contractual cash flows not expected to be collected |  | (5,385)
Expected cash flows at acquisition |  | 10,069
Interest component of expected cash flows |  | (793)
Fair value of acquired loans |  | 9,276
Merchants Bancshares, Inc. [Member] | Acquired Non Impaired Loans [Member] |  |
Summary of loans acquired [Abstract] |  |
Contractually required principal and interest at acquisition |  | 1,872,574
Contractual cash flows not expected to be collected |  | (14,753)
Expected cash flows at acquisition |  | 1,857,821
Interest component of expected cash flows |  | (378,940)
Fair value of acquired loans |  | $ 1,478,881

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- Definition The acquirer's estimate, at acquisition, of the amount and timing of undiscounted principal, interest, and other cash flows not expected to be collected. + References No definition available. + Details
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- Definition The investor's estimate, at acquisition, of the amount and timing of the interest component of expected cash flows for loans acquired in transfer not accounted for as debt securities. + References No definition available. + Details
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