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MANDATORILY REDEEMABLE PREFERRED SECURITIES (Details) $ in Millions |  | 6 Months Ended
--- | --- | ---
Sep. 16, 2019 USD ($) | Jun. 30, 2020 USD ($) Trust
Mandatorily Redeemable Preferred Securities [Abstract] |  |
Number of unconsolidated subsidiary business trusts owned | Trust |  | 2
Business Trust [Member] |  |
Mandatorily Redeemable Preferred Securities [Abstract] |  |
Percent ownership of unconsolidated subsidiary trusts |  | 100.00%
MBVT Statutory Trust I [Member] |  |
Mandatorily Redeemable Preferred Securities [Abstract] |  |
Redemption of debentures and associated preferred securities | $ 20.6 |
Kinderhook Capital Trust [Member] |  |
Mandatorily Redeemable Preferred Securities [Abstract] |  |
Redemption of debentures and associated preferred securities | $ 2.1 |
Preferred Debt [Member] | Community Capital Trust IV [Member] |  |
Terms of preferred securities for each trust [Abstract] |  |
Issuance date |  | Dec. 08, 2006
Par amount |  | $ 75.0
Effective interest rate |  | 1.96%
Maturity date |  | Dec. 15, 2036
Call price |  | Par
Preferred Debt [Member] | Community Capital Trust IV [Member] | LIBOR [Member] |  |
Terms of preferred securities for each trust [Abstract] |  |
Term of variable rate |  | 3 months
Variable interest rate, basis spread |  | 1.65%
Preferred Debt [Member] | Steuben Statutory Trust II [Member] |  |
Terms of preferred securities for each trust [Abstract] |  |
Issuance date |  | Jul. 16, 2007
Par amount |  | $ 2.0
Effective interest rate |  | 1.86%
Maturity date |  | Sep. 15, 2037
Call price |  | Par
Preferred Debt [Member] | Steuben Statutory Trust II [Member] | LIBOR [Member] |  |
Terms of preferred securities for each trust [Abstract] |  |
Term of variable rate |  | 3 months
Variable interest rate, basis spread |  | 1.55%

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