Commitments and Contingencies - Additional Information (Detail) $ in Millions			3 Months Ended		6 Months Ended
	May. 08, 2015 Complaints	Apr. 21, 2015 Plaintiff	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Jun. 30, 2015 USD ($)
Loss Contingencies [Line Items]
Number of plaintiffs | Plaintiff		3
Central District Of California [Member]
Loss Contingencies [Line Items]
Number of putative class action complaints filed | Complaints	1
Other Operating Expenses [Member]
Loss Contingencies [Line Items]
Pre-tax loss contingency amount			$ 11.3	$ 5.2	$ 16.5
Tax benefit on loss contingency					5.5
Net of tax loss contingency amount					$ 11.0