Quarterly report pursuant to Section 13 or 15(d)

Commitments and Contingencies - Additional Information (Detail)

v3.8.0.1
Commitments and Contingencies - Additional Information (Detail) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2017
Oct. 01, 2016
Sep. 30, 2017
Oct. 01, 2016
Commitments and Contingencies Disclosure [Abstract]        
Facility rent expense $ 430 $ 437 $ 1,289 $ 1,241