Weighted Average Contractual Life and Exercise Price (Detail) (USD $)	12 Months Ended
Dec. 31, 2012
Number of Options
Options vested	3,348,935
Weighted Average Remaining Contractual Life
Options outstanding	4 years 9 months 18 days
Options vested	4 years 9 months 18 days
Weighted Average Exercise Price
Options vested	$ 1.23

Share Based Compensation Arrangement By Share Based Payment Award Options Vested Number

No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Options Vested Weighted Average Exercise Price

+ References

No definition available.

+ Details

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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