Debt Debt Maturities (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Line of Credit Facility [Line Items]
Interest paid	$ 132.3	$ 414.2	$ 404.4
Debt Instrument, Unamortized Discount (Premium), Net	$ 89.0