Stock Option Activity (Detail) (USD $)	9 Months Ended
Sep. 30, 2013
Number of Shares Issuable
Balance, Ending	4,748,049
Weighted-average exercise price
Balance, Ending	$ 1.30
Stock Option
Number of Shares Issuable
Balance, Beginning	5,710,125
Granted	0
Exercised	0
Expired	(962,076)
Balance, Ending	4,748,049
Weighted-average exercise price
Balance, Beginning	$ 1.10
Granted	$ 0
Exercised	$ 0
Expired	$ 0.13
Balance, Ending	$ 1.30

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

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

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-Name Accounting Standards Codification

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- Definition

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

+ References

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- Definition

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

+ References

No definition available.

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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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No definition available.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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