Investment Securities - Summary of Amortization Cost and Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Available-for-sale Securities
Available-for-Sale:
Total Amortized Cost	$ 119,503	$ 143,194
Gross Unrealized Gains	1,296	2,140
Gross Unrealized Losses	(678)	(1,024)
Total Fair Value	120,121	144,310
Available-for-sale Securities \| Obligations of U.S. Government sponsored enterprises
Available-for-Sale:
Total Amortized Cost	22,182	22,218
Gross Unrealized Gains	141	227
Gross Unrealized Losses	(98)	(40)
Total Fair Value	22,225	22,405
Available-for-sale Securities \| Municipal securities
Available-for-Sale:
Total Amortized Cost	9,318	11,706
Gross Unrealized Gains	340	329
Gross Unrealized Losses	(23)	(54)
Total Fair Value	9,635	11,981
Available-for-sale Securities \| SBA pool securities
Available-for-Sale:
Total Amortized Cost	13,031	14,142
Gross Unrealized Gains	6	0
Gross Unrealized Losses	(127)	(230)
Total Fair Value	12,910	13,912
Available-for-sale Securities \| Residential mortgage-backed securities issued by GSE's
Available-for-Sale:
Total Amortized Cost	50,251	64,141
Gross Unrealized Gains	803	1,584
Gross Unrealized Losses	(76)	(95)
Total Fair Value	50,978	65,630
Available-for-sale Securities \| Commercial mortgage-backed securities
Available-for-Sale:
Total Amortized Cost	24,721	30,987
Gross Unrealized Gains	6	0
Gross Unrealized Losses	(354)	(605)
Total Fair Value	24,373	30,382
Held-to-maturity Securities
Held-to-Maturity:
Amortized Cost	21,689	16,583
Gross Unrealized Gains	152	160
Gross Unrealized Losses	(156)	(209)
Fair Value	21,685	16,534
Held-to-maturity Securities \| Municipal securities
Held-to-Maturity:
Amortized Cost	8,588	1,588
Gross Unrealized Gains	53	0
Gross Unrealized Losses	0	(52)
Fair Value	8,641	1,536
Held-to-maturity Securities \| Residential mortgage-backed securities issued by GSE's
Held-to-Maturity:
Amortized Cost	9,100	10,899
Gross Unrealized Gains	99	160
Gross Unrealized Losses	(156)	(157)
Fair Value	9,043	10,902
Held-to-maturity Securities \| Commercial mortgage-backed securities
Held-to-Maturity:
Amortized Cost	4,001	4,096
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	$ 4,001	$ 4,096

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount of debt securities categorized neither as held-to-maturity nor trading.

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Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity.

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Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity.

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Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as held-to-maturity.

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