Investment Securities - Amortized cost and estimated fair value of securities with gross unrealized gains and losses (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Available-for-Sale Portfolio
Amortized cost	$ 19,194	$ 19,974
Gross unrealized gains	122	101
Gross unrealized losses	(32)	(107)
Fair Value	19,284	19,968
Held-to-Maturity Portfolio
Amortized cost	9,556	12,979
Gross unrealized gains	$ 248	244
Gross unrealized losses		(1)
Fair Value	$ 9,804	13,222
U.S. Government and agency obligations
Available-for-Sale Portfolio
Amortized cost	6,077	$ 6,000
Gross unrealized gains	$ 12
Gross unrealized losses		$ (32)
Fair Value	$ 6,089	5,968
Held-to-Maturity Portfolio
Amortized cost	3,405	6,793
Gross unrealized gains	$ 102	$ 129
Gross unrealized losses
Fair Value	$ 3,507	$ 6,922
Mortgage-backed securities - residential
Available-for-Sale Portfolio
Amortized cost	13,117	13,974
Gross unrealized gains	110	101
Gross unrealized losses	(32)	(75)
Fair Value	13,195	14,000
Held-to-Maturity Portfolio
Amortized cost	1,504	1,535
Gross unrealized gains	$ 39	$ 39
Gross unrealized losses
Fair Value	$ 1,543	$ 1,574
State and Municipal securities
Held-to-Maturity Portfolio
Amortized cost	4,647	4,651
Gross unrealized gains	$ 107	76
Gross unrealized losses		(1)
Fair Value	$ 4,754	$ 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
-Paragraph 2
-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
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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
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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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