Equity and Accumulated Other Comprehensive Loss, Net (7.375% Series H Cumulative Redeemable Preferred Stock Narrative) (Details) - Series H Preferred Stock and Unit $ / shares in Units, $ in Millions				12 Months Ended
	Jun. 30, 2014 $ / shares	Apr. 07, 2014 USD ($) shares	Mar. 26, 2014 USD ($) $ / shares shares	Dec. 31, 2016 quarter $ / shares shares	Dec. 31, 2015 $ / shares shares	Apr. 08, 2016 shares
Class of Stock [Line Items]
Preferred stock, shares issued (in shares) | shares		2,000,000	12,000,000	14,600,000	14,600,000	14,600,000
Preferred stock, dividend rate			7.375%	7.375%	7.375%
Gross proceeds from issuance of redeemable preferred stock | $		$ 353.3	$ 289.3
Annual rate of dividend per share (in dollars per share)			$ 1.84375	$ 1.84375
Preferred stock, liquidation preference per share/unit (in dollars per share)			$ 25	25	$ 25
Preferred stock dividends per share declared (in dollars per share)	$ 0.48655
Preferred stock, redemption price per share (in dollars per share)				$ 25.00
Number of quarters with no dividends triggering voting rights | quarter				6
Shares issued upon conversion (in shares) | shares				0.9632
Over Allotment Option
Class of Stock [Line Items]
Preferred stock, shares issued (in shares) | shares		600,000