Non-Controlling Interests, Preferred Shares, Common Shares and Common Shares in Treasury - Effect of Company's Equity Derivative Instruments on Net Income (Loss) (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Derivatives, Fair Value [Line Items]
Gain (loss) on equity derivative instruments	$ 0	$ 21,926	$ (40,157)
Warrants [Member] | Gain (loss) on equity derivative instruments [Member]
Derivatives, Fair Value [Line Items]
Gain (loss) on equity derivative instruments		$ 21,900	$ (40,100)