Description of the Business and Summary of Significant Accounting Policies - Minimum Guarantees (Details) - Payment guarantee - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Guarantor Obligations [Line Items]
Accrued liabilities	$ 47.4	$ 48.7
Other long-term liabilities	117.6	146.8
Total minimum guarantee obligations	$ 165.0	$ 195.5
Weighted average remaining term (in years)	3 years	5 years
Expected future payments, 2018	$ 47.4	$ 48.7
Expected future payments, 2019	45.5
Expected future payments, 2020	44.9
Expected future payments, 2021	13.4
Expected future payments, 2022	13.8
Expected future payments, 2023	$ 0.0

License Agreements, Guaranteed Obligations, Term

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Other Commitments, Noncurrent

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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