Investment Securities - Summary of available-for-sale and held-to-maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Available-for-sale Securities
Available-for-Sale Securities, Amortized Cost	$ 283,586	$ 296,681
Available-for-Sale Securities, Gross Unrealized Gains	6,695	1,543
Available-for-Sale Securities, Gross Unrealized Losses	(227)	(4,148)
Available-for-Sale Securities, Fair Value	290,054	294,076
Held-to-Maturity Securities
Held-to-Maturity Securities, Amortized Cost	481	526
Held-to-Maturity Securities, Gross Unrealized Gains	0	0
Held-to-Maturity Securities, Gross Unrealized Losses	0	0
Held-to-Maturity Securities, Fair Value	481	526
Obligations of U.S. government corporations and agencies [Member]
Available-for-sale Securities
Available-for-Sale Securities, Amortized Cost	2,519	2,519
Available-for-Sale Securities, Gross Unrealized Gains	12	2
Available-for-Sale Securities, Gross Unrealized Losses	0	(18)
Available-for-Sale Securities, Fair Value	2,531	2,503
Mortgage-backed - residential
Available-for-sale Securities
Available-for-Sale Securities, Amortized Cost	80,965	76,165
Available-for-Sale Securities, Gross Unrealized Gains	1,233	111
Available-for-Sale Securities, Gross Unrealized Losses	(118)	(1,566)
Available-for-Sale Securities, Fair Value	82,080	74,710
REMICs [Member]
Available-for-sale Securities
Available-for-Sale Securities, Amortized Cost	2,072	2,712
Available-for-Sale Securities, Gross Unrealized Gains	15	4
Available-for-Sale Securities, Gross Unrealized Losses	0	(7)
Available-for-Sale Securities, Fair Value	2,087	2,709
Collateralized mortgage obligations [Member]
Available-for-sale Securities
Available-for-Sale Securities, Amortized Cost	89,802	103,026
Available-for-Sale Securities, Gross Unrealized Gains	997	124
Available-for-Sale Securities, Gross Unrealized Losses	(91)	(1,689)
Available-for-Sale Securities, Fair Value	90,708	101,461
Preferred stock
Available-for-sale Securities
Available-for-Sale Securities, Amortized Cost	0
Available-for-Sale Securities, Gross Unrealized Gains	1
Available-for-Sale Securities, Gross Unrealized Losses	0
Available-for-Sale Securities, Fair Value	1
Corporate bonds [Member]
Available-for-sale Securities
Available-for-Sale Securities, Amortized Cost	12,902	12,910
Available-for-Sale Securities, Gross Unrealized Gains	86	44
Available-for-Sale Securities, Gross Unrealized Losses	(18)	(148)
Available-for-Sale Securities, Fair Value	12,970	12,806
Obligations of state and political subdivisions [Member]
Available-for-sale Securities
Available-for-Sale Securities, Amortized Cost	95,326	99,349
Available-for-Sale Securities, Gross Unrealized Gains	4,351	1,258
Available-for-Sale Securities, Gross Unrealized Losses	0	(720)
Available-for-Sale Securities, Fair Value	99,677	99,887
Held-to-Maturity Securities
Held-to-Maturity Securities, Amortized Cost	444	475
Held-to-Maturity Securities, Gross Unrealized Gains	0	0
Held-to-Maturity Securities, Gross Unrealized Losses	0	0
Held-to-Maturity Securities, Fair Value	444	475
FHLMC certificates [Member]
Held-to-Maturity Securities
Held-to-Maturity Securities, Amortized Cost	6	8
Held-to-Maturity Securities, Gross Unrealized Gains	0	0
Held-to-Maturity Securities, Gross Unrealized Losses	0	0
Held-to-Maturity Securities, Fair Value	6	8
FNMA certificates [Member]
Held-to-Maturity Securities
Held-to-Maturity Securities, Amortized Cost	23	31
Held-to-Maturity Securities, Gross Unrealized Gains	0	0
Held-to-Maturity Securities, Gross Unrealized Losses	0	0
Held-to-Maturity Securities, Fair Value	23	31
GNMA certificates [Member]
Held-to-Maturity Securities
Held-to-Maturity Securities, Amortized Cost	8	12
Held-to-Maturity Securities, Gross Unrealized Gains	0	0
Held-to-Maturity Securities, Gross Unrealized Losses	0	0
Held-to-Maturity Securities, Fair Value	$ 8	$ 12

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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