INVESTMENT SECURITIES - Narrative (Details) $ in Thousands	3 Months Ended
Mar. 31, 2021 USD ($) security	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)
Debt Securities, Available-for-sale [Line Items]
Gain on investments	$ 145
Loss adjustment on equity securities		$ (40)
Number of investment securities \| security	14
Investment securities	$ 407,690		$ 466,465
Proceeds from sale of investment securities	75,736	0
Debt Securities
Debt Securities, Available-for-sale [Line Items]
Investment securities	75,600
Proceeds from sale of investment securities	75,700	$ 0
Collateral Pledged
Debt Securities, Available-for-sale [Line Items]
Investment securities pledged to secure public funds, fair value	$ 301,600		$ 398,700

Number of Investment Securities

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Amount 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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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 unrealized loss on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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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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