Derivative Instruments (Detail) - Schedule of Derivative Instruments Designated as Hedges of the Net Investment in a Foreign Operation (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012		Mar. 31, 2011
Weighted average of U.S. dollar equivalent of foreign denominated net assets	$ 1,893,401		$ 1,429,874
Derivative gains (losses) (1)	$ (37,872)	[1]	$ (41,409)	[1]

[1] Derivative gains (losses) from derivative instruments designated as hedges of the net investment in a foreign operation are recorded in the cumulative translation adjustment account within AOCI for each period.