Supplemental Cash Flow Information (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Supplemental Cash Flow Elements [Abstract]
Payments of interest and commitment fees	$ 45.8	$ 14.2
Interest Paid, Capitalized	6.0	3.0
Incurred liabilities for fixed and intangible asset additions	57.5	$ 73.7
Other Asset Additions Incurred but Not yet Paid	$ 0.3