Investment securities available for sale - Amortized cost and fair value of investment securities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 38,474	$ 46,700
Gross Unrealized Gains	828	352
Gross Unrealized Losses	(221)	(115)
Fair Value	39,081	46,937
U.S. Government Agencies Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	12,706	14,797
Gross Unrealized Gains	154	57
Gross Unrealized Losses	(3)	(9)
Fair Value	12,857	14,845
Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	17,989	25,124
Gross Unrealized Gains	631	204
Gross Unrealized Losses		(26)
Fair Value	18,620	25,302
Subordinated Debt [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	7,779	6,779
Gross Unrealized Gains	43	91
Gross Unrealized Losses	(218)	(80)
Fair Value	$ 7,604	$ 6,790

Amount, before tax, of unrealized gain 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).

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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).

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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).

+ References

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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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