Income Taxes Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Deferred tax assets:
Inventories	$ 5.2	$ 8.8
Income tax credits	21.0	30.9
Accrued liabilities	17.2	20.8
Pension	55.8	77.6
Post retirement and post employment benefits	6.5	10.0
Stock-based compensation	13.4	17.5
Net operating loss carryforwards	19.0	27.2
Miscellaneous other	10.7	7.5
Gross deferred tax assets	148.8	200.3
Valuation allowance	(19.4)	(22.6)
Total deferred tax assets, net of valuation allowance	129.4	177.7
Deferred tax liabilities:
Acquisition basis difference	(116.5)	(162.1)
Property, plant, and equipment	(30.3)	(46.3)
Total deferred tax liabilities	(146.8)	(208.4)
Non-current tax assets (included in Other long-term assets)	6.3	10.5
Non-current tax liabilities (included in Other Non-Current Liabilities)	(23.7)	(41.2)
TOTAL NET DEFERRED TAX LIABILITY	$ (17.4)	$ (30.7)