Securities - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 13,968	$ 18,130
Fair value	14,300	18,516
Minimum percentage of securities hold		10.00%
Issued by U.S. government-sponsored entities and agencies
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 13,968	$ 18,130
Minimum percentage of securities hold	10.00%

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References+ Details

Amount of debt securities categorized neither as held-to-maturity nor trading.

+ References

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Reference 9: http://www.xbrl.org/2003/role/presentationRef

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+ Details