Securities - Amortized Cost and Fair Value of Available-for-sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Debt securities available-for-sale:
Amortized Cost	$ 116,141	$ 131,046
Gross Unrealized Gains	274	209
Gross Unrealized Losses	(880)	(1,833)
Fair Value	115,535	129,422
U.S. Government-sponsored enterprises (GSEs) [Member]
Debt securities available-for-sale:
Amortized Cost	16,217	18,279
Gross Unrealized Gains	3	8
Gross Unrealized Losses	(309)	(564)
Fair Value	15,911	17,723
Municipal securities [Member]
Debt securities available-for-sale:
Amortized Cost	8,341	8,182
Gross Unrealized Gains	63	16
Gross Unrealized Losses	(41)	(179)
Fair Value	8,363	8,019
Other debt securities [Member]
Debt securities available-for-sale:
Amortized Cost	973
Gross Unrealized Gains	0
Gross Unrealized Losses	(35)
Fair Value	938
Mortgage-backed securities [Member]
Debt securities available-for-sale:
Amortized Cost	90,610	104,585
Gross Unrealized Gains	208	185
Gross Unrealized Losses	(495)	(1,090)
Fair Value	$ 90,323	$ 103,680

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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