Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2010
Commitments and Contingencies Disclosure [Line Items]
Minimum term of non-cancellable operating leases	1 year
Expiration of non-cancellable operating leases maximum year	2020
Financing for leasehold improvement		$ 1.1
Outstanding liability related to leasehold improvements	$ 0.4
Accrued liabilities
Commitments and Contingencies Disclosure [Line Items]
Leasehold Improvements reflected in Accrued liabilities	0.1
Other non-current liabilities
Commitments and Contingencies Disclosure [Line Items]
Leasehold Improvements reflected in Other non-current liabilities	$ 0.3