Facility Lease Exit - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Sep. 30, 2014	Mar. 31, 2016
Facility Lease Exit Disclosure [Line Items]
Notice period to surrender remaining leased space		90 days
3rd Amendment, Lease exit costs associated with 650 E. Kendall.
Facility Lease Exit Disclosure [Line Items]
Lease exit expense incurred	$ 15.6
Leased space surrendering date		May 29, 2015
3rd Amendment, Lease exit costs associated with 650 E. Kendall. | Leasehold Improvements
Facility Lease Exit Disclosure [Line Items]
Additional charge to depreciation expense due to revision of estimated useful life		$ 1.4
3rd Amendment, Lease exit costs associated with 650 E. Kendall. | Deferred Rent And Leasehold Improvement
Facility Lease Exit Disclosure [Line Items]
Additional charge to depreciation expense due to revision of estimated useful life		$ 1.7