Consolidated Statements of Comprehensive Income (USD $)	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net income	$ 512,300,000		$ 138,280,000		$ 294,840,000
Other comprehensive income (loss):
Unrecognized gains (losses) on equity investments	389,000		(173,000)		403,000
Unrecognized gains (losses) on cash flow hedges	4,409,000		1,898,000		1,604,000
Unrecognized actuarial gain/(loss)	(137,000)		1,522,000		(226,000)
Unrecognized gains (losses) on foreign currency translation	(71,964,000)		(23,247,000)		(881,000)
Total other comprehensive income	(67,303,000)		(20,000,000)		900,000
Total comprehensive income	444,997,000		118,280,000		295,740,000
Net and comprehensive income attributable to noncontrolling interests	(14,678,000)	[1]	(13,267,000)	[1]	(2,415,000)	[1]
Comprehensive income attributable to controlling interests	$ 430,319,000		$ 105,013,000		$ 293,325,000

[1] Includes amounts attributable to redeemable noncontrolling interests