Restricted Cash - Additional Information (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash balance	$ 1,469	$ 700
Shelton Lease [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash balance	$ 700
Lease term	2017-10
Stamford Lease [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Lease term	2023-10
Letter of credit, remaining amount	$ 769
Letter of credit, remaining amount after three years	$ 408