Noncontrolling Interests (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Changes in the noncontrolling interests
Beginning Balance			$ 40,900,000	$ 46,600,000
Distributions to noncontrolling interests			(8,100,000)	(11,300,000)
Comprehensive income:
Net Income attributable to noncontrolling interests	1,700,000	2,400,000	3,500,000	5,000,000
Other comprehensive income, net of tax			0	0
Comprehensive income			3,500,000	5,000,000
Ending Balance	$ 36,300,000	$ 40,300,000	$ 36,300,000	$ 40,300,000