Investment Securities - Held-to-maturity (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Amortized cost and fair values of investment securities held-to-maturity
Amortized Cost	$ 53,903	$ 54,538
Unrealized Gain	1,716	1,600
Unrealized Loss	(207)	(267)
Securities held-to-maturity, fair value	55,412	55,871
Municipal securities
Amortized cost and fair values of investment securities held-to-maturity
Amortized Cost	53,903	54,538
Unrealized Gain	1,716	1,600
Unrealized Loss	(207)	(267)
Securities held-to-maturity, fair value	$ 55,412	$ 55,871

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

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- Definition

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

+ References

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Fair value of investments in debt securities classified as held-to-maturity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

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-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

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-Section 50

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