Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount classified as assets attributable to disposal group held for sale or disposed of.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Goodwill and Intangible Assets - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Assets held for sale	$ 8.2	$ 8.2	$ 26.0
Weighted average useful life		2 years	3 years
Minimum
Finite-Lived Intangible Assets [Line Items]
Amortization period		1 year
Maximum
Finite-Lived Intangible Assets [Line Items]
Amortization period		8 years
Trading rights
Finite-Lived Intangible Assets [Line Items]
Impairment charges	$ 0.7	$ 0.7
Amortization period		4 years	5 years