Commitments and Contingencies - Summary of Consideration Assigned to Identifiable Elements (Detail) (USD $) In Thousands, unless otherwise specified	0 Months Ended
	Sep. 05, 2014	Apr. 24, 2014
Gain Contingencies [Line Items]
Litigation settlement amount	$ 108,712	$ 283,000
Implied license [Member]
Gain Contingencies [Line Items]
Litigation settlement amount	85,132
Other damages [Member]
Gain Contingencies [Line Items]
Litigation settlement amount	18,714
Interest income [Member]
Gain Contingencies [Line Items]
Litigation settlement amount	$ 4,866