Share Based Payment (Detail) - Stock option activity (USD $)	9 Months Ended
Sep. 30, 2012
Outstanding at December 31, 2011	301,634
Outstanding at December 31, 2011 (in Dollars per share)	$ 18.57
Granted	506,895
Granted (in Dollars per share)	$ 2.92
Forfeited	(41,175)
Forfeited (in Dollars per share)	$ 3.06
Expired	(11,368)
Expired (in Dollars per share)	$ 78.97
Outstanding at September 30, 2012	755,986
Outstanding at September 30, 2012 (in Dollars per share)	$ 8.01
Outstanding at September 30, 2012	8.69
Outstanding at September 30, 2012 (in Dollars)	$ 18,823
Exercisable at September 30, 2012	286,101
Exercisable at September 30, 2012 (in Dollars per share)	$ 16.40
Exercisable at September 30, 2012	7.46

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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

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

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(c), d(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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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.

+ 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 (c)(1)(iii)

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- Definition

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

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

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

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

+ References

No definition available.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

+ References

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- Definition

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.

+ References

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

-Publisher FASB

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Subparagraph (c)(1)(i)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The weighted average period between the balance sheet date and expiration for all awards outstanding under the plan, which may be expressed in a decimal value for number of years.

+ 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 of the plan that expired.

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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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Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

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The weighted average remaining life of the exercisable stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

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