Summary of Stock Option Activity and Related Information, without Regard for Estimated Forfeitures (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	6 Months Ended
Jun. 30, 2012
Shares
Options outstanding Beginning Balance	362
Options granted
Options exercised
Options forfeited	(161)
Options outstanding Ending Balance	201
Weighted Average Exercise Price
Options outstanding Beginning Balance	$ 10.07
Options granted
Options exercised
Options forfeited	$ 18.13
Options outstanding Ending Balance	$ 3.60

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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-Name Accounting Standards Codification

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Net number of share options (or share units) granted during the period.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Number of share options (or share units) exercised during the current period.

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