Investment securities HTM Contractual Maturity Table (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
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	765
Securities held to maturity, debt securities due after five years through ten years, amortized cost	105,931
Securities held to maturity, debt securities due after ten years, amortized cost	195,245
Total held to maturity debt securities, amortized Cost	301,941	175,210
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	774
Securities held to maturity, debt securities due after five years through ten years, fair value	106,998
Securities held to maturity, debt securities due after ten years, fair value	200,110
Investment securities held to maturity, fair value	$ 307,882	$ 169,889
Ratio of Fair Value to Amortized Cost, HTM	102.00%

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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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 after the tenth fiscal year following the latest fiscal year.

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