INVESTMENT SECURITIES - Amortized cost and estimated fair value of available-for-sale securities excluding SBIC (Details) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019 USD ($) security	Dec. 31, 2018 USD ($) security
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 54,576	$ 45,723
Fair Value	53,610	43,695
Debt available for sale securities pledged as collateral	$ 5,300	$ 5,400
Threshold Percentage Of Shareholders Equity Amount Held As Securities By One Issuer	10.00%	10.00%
Unrealized loss	$ 1,072	$ 2,039
Number of securities in continuous unrealized loss position for more than twelve months \| security	25
Available for sale securities, excluding SBIC
Debt Securities, Available-for-sale [Line Items]
Due within one year through five years amortized cost	$ 555
Due within one year through five years fair value	558
Mortgage-related securities, amortized cost	54,021
Mortgage-related securities, fair value	53,052
Amortized Cost	54,576
Fair Value	$ 53,610
Number of securities in unrealized loss position \| security	30	33

Available For Sale Securities Debt Maturities Within One Through Five Years Amortized Cost

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Available For Sale Securities Debt Maturities Within One Through Five Years Fair Value

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- Definition

Represents the carrying value of securities pledged to secure various public deposits and credit facilities of the Company.

+ References

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Represents the threshold percentage of shareholders equity amount held as securities by one issuer.

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- Definition

Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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Amortized cost 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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-Publisher FASB
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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), without single maturity date and not allocated over maturity grouping.

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), without single maturity date and not allocated over maturity grouping.

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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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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer.

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position.

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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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