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MANDATORILY REDEEMABLE PREFERRED SECURITIES (Details) $ in Millions |  |  | 9 Months Ended
--- | --- | --- | ---
Sep. 15, 2020 USD ($) | Sep. 16, 2019 USD ($) | Sep. 30, 2020 USD ($) trust
Mandatorily Redeemable Preferred Securities [Abstract] |  |  |
Number of unconsolidated subsidiary business trusts owned | trust |  |  | 1
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 |
Steuben Statutory Trust |  |  |
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 |  |  | 1.90%
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%

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