Investment securities HTM Contractual Maturity Table (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Amortized cost and fair values of investment securities held to maturity
Securities held to maturity, debt securities due in one year or less, amortized cost	$ 0
Securities held to maturity, debt securities due after one year through five years, amortized cost	233
Securities held to maturity, debt securities due after five years through ten years, amortized cost	49,861
Securities held to maturity, debt securities due after ten years, amortized cost	75,001
Total held to maturity debt securities, amortized Cost	125,095	39,877
Securities held to maturity, debt securities due in one year or less, fair value	0
Securities held to maturity, debt securities due in one year through five years, fair value	232
Securities held to maturity, debt securities due after five years through ten years, fair value	48,655
Securities held to maturity, debt securities due after ten years, fair value	72,602
Investment securities held to maturity, fair value	$ 121,489	$ 39,679
Ratio of Fair Value to Amortized Cost, HTM	97.10%

Ratio of Fair Value to Amortized Cost, HTM

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

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Amount of held-to-maturity debt securities at fair value maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year.

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Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized, and fair value hedge accounting adjustments, maturing in the fifth through tenth fiscal year following the latest fiscal year.

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Amount of held-to-maturity debt securities at fair value maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year.

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