Securities (Securities held to maturity (debt maturities) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Amortized Cost
Due in 1 year or less	$ 0
Due in 1 to 5 years	1,281
Due in 5 to 10 years	10,200
Due after 10 years	36,315
Total debt securities	47,796
Mortgage-backed securities	6,045
Total investment securities	53,841	55,502
Estimated Fair Value
Due in 1 year or less	0
Due in 1 to 5 years	1,281
Due in 5 to 10 years	10,200
Due after 10 years	36,315
Total debt securities	47,796
Mortgage-backed securities	6,097
Estimated Fair Value	$ 53,893	$ 55,982

Held-to-maturity Securities, Excluding Securities without Single Maturity Date, Fair Value

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Held-to-maturity Securities, Excluding Securities without Single Maturity Date, Net Carrying Amount

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

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Amount of held-to-maturity debt securities at fair value that do not have a single maturity date and which the entity has decided to disclose separately rather than allocating the fair value over several maturity groupings.

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

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