Investment Securities Held-to-Maturity (Details 1) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Company's securities held-to-maturity
Within one year, Amortized Cost	$ 6,780
After one but within five years, Amortized Cost	205,981
After five but within ten years, Amortized Cost	62,472
More than 10 years, Amortized Cost	274
Total, Amortized Cost	275,507
Within one year, Fair Value	6,865
After one but within five years, Fair Value	210,897
After five but within ten years, Fair Value	63,880
More than 10 years, Fair Value	282
Total, Fair Value	$ 281,924

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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 in the next fiscal year through the fifth fiscal year following the latest fiscal year.

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

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This item represents the total of all debt securities grouped by maturity dates, at fair value, which are categorized as held-to-maturity.

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