DERIVATIVE FINANCIAL INSTRUMENTS - Notional Amounts and Estimated Fair Values, Non-hedging (Details) - Not Designated as Hedging Instrument - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Derivative disclosures
Asset Derivative	$ 1,824	$ 2,010
Liability Derivative	1,848	2,092
Offsetting derivative assets	(369)	(698)
Offsetting derivative liabilities	(369)	(698)
Net derivative assets in the consolidated balance sheets	1,455	1,312
Net derivative liabilities in the consolidated balance sheets	1,479	1,394
Interest Rate Swaps \| Financial Institution
Derivative disclosures
Notional Amount	173,304	185,637
Asset Derivative	1,326	698
Liability Derivative	448	1,389
Interest Rate Swaps \| Customer
Derivative disclosures
Notional Amount	173,304	185,637
Asset Derivative	423	1,307
Liability Derivative	1,325	698
Interest Rate Caps and Collars \| Financial Institution
Derivative disclosures
Notional Amount	37,466	16,482
Asset Derivative	75	5
Interest Rate Caps and Collars \| Customer
Derivative disclosures
Notional Amount	37,446	16,482
Liability Derivative	$ 75	$ 5

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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