Commitments and Contingencies - Additional Information (Detail)	9 Months Ended
Sep. 30, 2015 LegalMatter
Loss Contingencies [Line Items]
Approximate number of federal district court actions alleged for patent infringement	60
Guarantee obligations, year term (in years)	30 years

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.

No definition available.

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