Investment Securities - Amortized cost and estimated fair value of securities with gross unrealized gains and losses (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Available-for-Sale Portfolio
Amortized cost	$ 17,620	$ 19,974
Gross unrealized gains	60	101
Gross unrealized losses	(28)	(107)
Fair Value	17,652	19,968
Held-to-Maturity Portfolio
Amortized cost	6,369	12,979
Gross unrealized gains	122	244
Gross unrealized losses	(2)	(1)
Fair Value	6,489	13,222
U.S. Government and agency obligations
Available-for-Sale Portfolio
Amortized cost	7,106	6,000
Gross unrealized gains	5
Gross unrealized losses	(4)	(32)
Fair Value	7,107	5,968
Held-to-Maturity Portfolio
Amortized cost		6,793
Gross unrealized gains		129
Gross unrealized losses
Fair Value		6,922
Mortgage-backed securities - residential
Available-for-Sale Portfolio
Amortized cost	10,514	13,974
Gross unrealized gains	55	101
Gross unrealized losses	(24)	(75)
Fair Value	10,545	14,000
Held-to-Maturity Portfolio
Amortized cost	802	1,535
Gross unrealized gains	18	39
Gross unrealized losses
Fair Value	820	1,574
State and Municipal securities
Held-to-Maturity Portfolio
Amortized cost	5,567	4,651
Gross unrealized gains	104	76
Gross unrealized losses	(2)	(1)
Fair Value	$ 5,669	$ 4,726

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
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This item represents the cost of debt and equity 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
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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 investments in debt securities classified as held-to-maturity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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