Analysis of Changes in Components of Accumulated Other Comprehensive Income (Loss) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2012
Other comprehensive income (loss):
Unrealized gain (loss) on investment securities	$ 1	$ 21
Less: reclassification for realized (loss) gain included in net loss	1	21
Other comprehensive income (loss)	$ 0	$ 0

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized loss realized upon the write-down of available-for-sale securities.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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