Components of Lease Exit Activity Recorded in Current Liabilities (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Facility Lease Exit Disclosure [Line Items]
Amounts accrued	$ 5,453	$ 9,301
Accretion Expense incurred	224
Lease exit costs
Facility Lease Exit Disclosure [Line Items]
Amounts accrued		$ 4,981
Accretion Expense incurred	224
Restructuring amounts paid	(5,477)
Additional expense incurred	$ 272