Equity and Accumulated Other Comprehensive Loss, Net (Ownership Interest In The Operating Partnership) (Details) $ in Millions	Dec. 31, 2015 USD ($) shares	Dec. 31, 2014 USD ($) shares
Class of Stock [Line Items]
Partners' capital account units	146,384,247	135,626,255
Percentage of total	98.10%	97.80%
Redeemable noncontrolling interest | $	$ 192.7	$ 179.0
Common stock conversion ratio	1
Common units held by third parties
Class of Stock [Line Items]
Common units held by third parties	1,421,314	1,463,814
Percentage of total	1.00%	1.10%
Incentive Units Held By Employees And Directors
Class of Stock [Line Items]
Incentive units held by employees and directors	1,412,012	1,549,847
Percentage of total	0.90%	1.10%
Noncontrolling Interests in Operating Partnership
Class of Stock [Line Items]
Partners' capital account units	149,217,573	138,639,916
Percentage of total	100.00%	100.00%