Consolidated Statements of Comprehensive Income (USD $)	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Statement of Comprehensive Income [Abstract]
Net income	$ 138,280,000		$ 294,840,000		$ 212,716,000
Other comprehensive income (loss):
Unrecognized gains (losses) on equity investments	(173,000)		403,000		(122,000)
Unrecognized gains (losses) on cash flow hedges	1,898,000		3,200,000		3,189,000
Reclassification adjustment realized in net income	0		(1,596,000)		(1,781,000)
Unrecognized actuarial gain/(loss)	1,522,000		(226,000)		(2,115,000)
Unrecognized gains (losses) on foreign currency translation	(23,247,000)		(881,000)		0
Total other comprehensive income	(20,000,000)		900,000		(829,000)
Total comprehensive income	118,280,000		295,740,000		211,887,000
Net and comprehensive income attributable to noncontrolling interests	(13,267,000)	[1]	(2,415,000)	[1]	(4,894,000)	[1]
Comprehensive income attributable to controlling interests	$ 105,013,000		$ 293,325,000		$ 206,993,000

[1] Includes amounts attributable to redeemable noncontrolling interests