The effect of liquidating LIFO (last in first out) inventory layers on income.

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Amount by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount of valuation reserve for inventory.

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The amount of LIFO (last in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

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Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense.

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Inventories Narrative (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Inventories Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2018
Inventory [Line Items]
LIFO inventory amount		$ 794.3	$ 821.2
Inventory valuation reserves		(88.5)	(121.5)
Effect of LIFO liquidation on income		0.8	(4.6)	$ (61.5)
Inventories, net		1,211.1	1,176.1
Adjustment from current cost to LIFO cost basis		2.9	43.1
ASU 2014-09
Inventory [Line Items]
Inventory valuation reserves					$ 11.8
Inventories, net		9.5			28.8
Adjustment from current cost to LIFO cost basis					(11.8)
ASU 2014-09 \| Transferred over Time
Inventory [Line Items]
Inventories, net		5.4			$ (34.2)
Titanium sponge inventory \| SEC Schedule, 12-09, Reserve, Inventory
Inventory [Line Items]
Inventory valuation charges	$ 11.3
Industrial titanium products \| SEC Schedule, 12-09, Reserve, Inventory
Inventory [Line Items]
Inventory valuation charges				$ 17.7
Net Realizable Value Reserve
Inventory [Line Items]
Inventory valuation reserves		$ (8.0)	$ (47.5)