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Business Segments - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 488.6			$ 0.0	$ 498.6	$ 0.0
Long-lived impairment charges
Restructuring Cost and Reserve [Line Items]
Restructuring charges	471.3
Facility shutdown, idling, and employee benefit costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	17.3
Employee severance
Restructuring Cost and Reserve [Line Items]
Restructuring charges		$ 1.0	$ 9.0
Inventory Valuation Reserve | Titanium Sponge Inventory
Restructuring Cost and Reserve [Line Items]
Inventory valuation charges	$ 11.3
High Performance Materials & Components
Restructuring Cost and Reserve [Line Items]
Increase (Decrease) in Assets					$ (521.0)

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Amount of restructuring charges, remediation cost, and asset impairment loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from charges to costs and expenses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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