v3.8.0.1

Derivative and Other Financial Instruments and Fair Value Measurements - Losses on Assets Recorded at Fair Value on Nonrecurring Basis (Detail) - USD ($) $ in Millions	3 Months Ended			12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value Assets And Liabilities Measured On Recurring Basis
Goodwill impairment		$ 33.6	$ 61.8	$ 33.6	$ 61.8	$ 0.0
Property, plant and equipment impairment	$ 40.5			40.5
RANA
Fair Value Assets And Liabilities Measured On Recurring Basis
Goodwill impairment				33.6	61.8
Fair Value, Measurements, Nonrecurring Basis \| RANA
Fair Value Assets And Liabilities Measured On Recurring Basis
Goodwill impairment				33.6	61.8
Property, plant and equipment impairment				40.5
Identifiable intangible assets impairment				10.1
Fair Value, Measurements, Nonrecurring Basis \| Cosmedicine
Fair Value Assets And Liabilities Measured On Recurring Basis
Identifiable intangible assets impairment					0.1
Inventories impairment				$ 0.1	$ 0.7

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+ References

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

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Real Industry, Inc. 10-K