Warrant Activity Under Plan (Detail) (Warrant, USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Warrant
Share Based Compensation Plans [Line Items]
Outstanding	85,620
Granted	0
Exercised	0
Forfeited/expired	0
Outstanding	85,620	85,620
Vested and expected to vest	85,620
Exercisable	0
Weighted - Average Exercise Price, Outstanding	$ 0.90
Weighted - Average Exercise Price, Outstanding	$ 0.9	$ 0.90
Weighted - Average Exercise Price, Vested and expected to vest	$ 0.9
Weighted - Average Exercise Price, Exercisable	$ 0
Weighted Average Remaining Contractual Term (In years), Outstanding	10 months 24 days	1 year 10 months 24 days
Weighted Average Remaining Contractual Term (In years), Vested and expected to vest	10 months 24 days
Weighted Average Remaining Contractual Term (In years), Exercisable	0 years
Aggregate Intrinsic Value, Outstanding	$ 0
Aggregate Intrinsic Value, Outstanding	0	0
Aggregate Intrinsic Value, Vested and expected to vest	0
Aggregate Intrinsic Value, Exercisable	$ 0

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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For presentations that combine terminations, 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 or that expired.

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Gross 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 remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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