Noncontrolling Interests (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Noncontrolling Interests
Earnings (losses) attributable to noncontrolling interest before tax	$ 44,800,000	$ 31,800,000	$ 93,100,000	$ 54,400,000
Earnings (losses) attributable to noncontrolling interest, tax benefit (expense)	1,100,000	(500,000)	(400,000)	(800,000)
Distributions paid to noncontrolling interest holders			45,809,000	40,172,000
Capital contribution from noncontrolling interests			$ 1,462,000	$ 3,387,000