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Face amount or stated value per share of common stock.

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-Publisher FASB
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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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Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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Significant Accounting Policies - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Jun. 30, 2016	Mar. 13, 2015	Mar. 10, 2015
JV
Variable Interest Entity, Not Primary Beneficiary, Disclosures [Abstract]
Ownership percentage			50.00%
VIE
Variable Interest Entity, Not Primary Beneficiary, Disclosures [Abstract]
Ownership percentage			50.00%
Minimum
Goodwill and intangible assets
Amortization period			1 year
Foreign currency translation and foreign currency forward contracts
Fixed assets, useful life			3 years
Maximum
Goodwill and intangible assets
Amortization period			8 years
Foreign currency translation and foreign currency forward contracts
Fixed assets, useful life			7 years
Investment Income and Other, Net
Foreign currency translation and foreign currency forward contracts
Gain (loss) on foreign currency transactions	$ 0.1	$ (1.8)	$ 1.0	$ (2.4)
Senior Secured Notes \| 6.875% Senior Secured Notes
Repurchases of debt
Interest rate (percent)	6.875%	6.875%	6.875%	6.875%	6.875%	6.875%	6.875%
Common Class A
Repurchases of common stock
Common stock, par value (in dollars per share)	$ 0.01		$ 0.01
Software
Goodwill and intangible assets
Amortization period			3 years