Net Loss Per Share - Additional Information (Detail)	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Outstanding warrants and equity awards were not included in diluted net loss per share calculation	34,400,000	37,200,000

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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+ Details