Fair Value Accounting (Details Textual) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012
Fair Value Accounting (Textual)
Decrease in other investment in FHLB stock	$ 130,000
Percentage of loans collateralize by real estate	More than 80

Percentage of company's loans collateral by real estate.

No definition available.

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration