Held for Sale (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	$ 8.8	$ (225.1)	$ (74.4)	$ (222.3)
Miami Fort and Zimmer [Member]
Disposal Group, Including Discontinued Operation, Inventory	24.0		24.0
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	3.0	(9.7)	2.2	(16.2)
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment	44.6		44.6
Disposal Group, Including Discontinued Operation, Assets	68.6		68.6
Disposal Group, Including Discontinued Operation, Accounts Payable	12.9		12.9
Disposal Group, Including Discontinued Operation, Accrued Income Tax Payable	4.9		4.9
Asset Retirement Obligation, Held for Sale	4.7		4.7
Disposal Group, Including Discontinued Operation, Other Liabilities	0.7		0.7
Disposal Group, Including Discontinued Operation, Liabilities	23.2		23.2
Subsidiaries [Member]
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	26.3	(835.3)	(37.4)	(789.2)
Subsidiaries [Member] | Miami Fort and Zimmer [Member]
Disposal Group, Including Discontinued Operation, Inventory	24.0		24.0
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	3.0	$ (9.7)	2.2	$ (16.2)
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment	44.6		44.6
Disposal Group, Including Discontinued Operation, Assets	68.6		68.6
Disposal Group, Including Discontinued Operation, Accounts Payable	12.9		12.9
Disposal Group, Including Discontinued Operation, Accrued Income Tax Payable	4.9		4.9
Asset Retirement Obligation, Held for Sale	3.7		3.7
Disposal Group, Including Discontinued Operation, Other Liabilities	0.7		0.7
Disposal Group, Including Discontinued Operation, Liabilities	$ 22.2		$ 22.2