Noncontrolling Interests Property Partnerships (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Activity of Noncontrolling Interests [Roll Forward]
Beginning Balance			$ 1,602,467
Capital contributions			1,089	$ 1,675
Net income	$ 9,264	$ 7,553	24,472	11,907
Accumulated other comprehensive income	(2,512)	(64)	(2,209)	(126)
Ending Balance	1,590,481		1,590,481
Property Partnerships Member
Activity of Noncontrolling Interests [Roll Forward]
Beginning Balance			1,602,467	726,132
Capital contributions			1,089	1,675
Net income			20,031	5,438
Accumulated other comprehensive income			(916)
Distributions			(34,022)	(12,149)
Ending Balance	$ 1,590,481	$ 721,096	$ 1,590,481	$ 721,096