Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash Flow Provided by (Used in) Operations Due to Changes in Operating Assets and Liabilities
Receivables, Net	$ (103.4)	$ (1,155.5)	$ (658.8)
Inventories, Net	(72.8)	(82.0)	(6.5)
Other Current Assets	(7.3)	4.2	0.8
Other Assets	(6.3)	1.9	(32.8)
Accounts Payable	(8.6)	76.2	27.0
Compensation and Employee Benefits	12.9	26.9	3.5
Income Taxes	(4.2)	(1.0)	18.9
Interest Payable	8.4	(4.1)	(1.7)
Other Accrued Liabilities	(17.0)	12.0	(16.6)
Other Noncurrent Liabilities	12.1	(4.8)	14.2
Total	(186.2)	(1,126.2)	(652.0)
Cash paid for interest and cash paid, net of refunds, for income taxes
Interest	126.8	125.0	81.8
Income Taxes	$ 18.5	$ 17.3	$ 15.9