Commitments and Contingencies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2016 USD ($) Contracts	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Commitments And Contingencies Disclosure [Line Items]
Capital lease assets	$ 64,200,000	$ 64,900,000
Assets fully depreciated	22,800,000	19,100,000
Capital leased assets, net book value	16,400,000	22,100,000
Rent expense under operating leases	$ 11,580,000	$ 9,362,000	$ 7,871,000
Contract One [Member]
Commitments And Contingencies Disclosure [Line Items]
Extended term of contract	Dec. 31, 2016
Contract Two [Member]
Commitments And Contingencies Disclosure [Line Items]
Extended term of contract	Aug. 31, 2017
Number of product supply contracts | Contracts	0
Purchases made under contract	$ 0
Minimum [Member]
Commitments And Contingencies Disclosure [Line Items]
Estimated life of capital lease	4 years
Noncancellable operating leases, renewal period	1 year
Maximum [Member]
Commitments And Contingencies Disclosure [Line Items]
Estimated life of capital lease	6 years
Noncancellable operating leases, renewal period	5 years