Investment Securities (Schedule of OTTI Changes) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011	Dec. 31, 2010
Investment Securities [Abstract]
Other than temporary impairment charges			$ 60	$ 18
Principal losses on variable rate CMO			272	285
Total other-than-temporary impairment charges			6,871		6,539	6,197
Total other-than-temporary impairment charges	$ 134	$ 66	$ 332	$ 303

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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- Definition

The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

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