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

Earnings Per Share - Additional Information (Detail)	12 Months Ended
Earnings Per Share - Additional Information (Detail)	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
0.50% convertible bonds due 2013 [Member]
Earnings Per Share Basic And Diluted [Line Items]
Common shares outstanding for convertible debt	5,624
Stock Options [Member]
Earnings Per Share Basic And Diluted [Line Items]
Portion of anti-dilutive shares in outstanding stock option	16,690,472	26,453,152	35,296,895