Investment Securities HTM Securities Amortized Cost and Fair Value (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Sep. 30, 2013	Dec. 31, 2012
Investment securities held to maturity:
Investment securities held to maturity at amortized cost	$ 125,095	$ 39,877
Investment securities held to maturity, gross unrealized gains	645	98
Investment securities held to maturity, gross unrealized losses	(4,251)	(296)
Investment securities held to maturity, fair value	121,489	39,679
Obligations of state and political subdivisions (municipal securities) [Member]
Investment securities held to maturity:
Investment securities held to maturity at amortized cost	125,095	39,877
Investment securities held to maturity, gross unrealized gains	645	98
Investment securities held to maturity, gross unrealized losses	(4,251)	(296)
Investment securities held to maturity, fair value	$ 121,489	$ 39,679

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

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

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-Name Accounting Standards Codification

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

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Amount of unrecognized gain before loss on investments in held-to-maturity securities.

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Amount of unrecognized loss before gain on investments in held-to-maturity securities. Excludes write-down for other than temporary impairment (OTTI).

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