Commitments and Contingencies (Details) $ in Millions	6 Months Ended
Jun. 30, 2019 USD ($)
Nielson Audio
Supply Commitment [Line Items]
Remaining aggregate obligation under the agreements with Nielsen Audio	$ 126.4

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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