Supplemental Disclosure of Cash Flow Information (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash paid during the period for:
Interest (net of amount capitalized)	$ 82.4	$ 78.7
Non-cash adjustments:
Accounts payable and property, plant and equipment	$ 90.0	$ 94.6