INVESTMENT SECURITIES - Proceeds from Sales of AFS Securities and Gross Gains and Gross Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Proceeds from sale of investment securities	$ 0	$ 59,464
Gross gains	0	519
Gross losses	40	180
Debt Securities, Available-for-sale [Line Items]
Loss on investment	(40)
Gain on investments		$ 339
Collateral Pledged
Debt Securities, Available-for-sale [Line Items]
AFS securities pledged to secure public funds, fair value	$ 377,000		$ 158,700

Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized and unrealized gain (loss) on investment.

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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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