Transactions between the Company and Related Parties - Related Party Transactions (Parenthetical) (Detail) - Bridgeview Facility [Member] $ in Thousands		9 Months Ended
	Oct. 03, 2018	Sep. 30, 2018 USD ($) ft²
Related Party Transaction [Line Items]
Lease of Bridgeview Facility | ft²		40,000
Monthly lease payments | $		$ 22
Subsequent Event [Member]
Related Party Transaction [Line Items]
Maximum rental escalation	2.00%
Lease term	15 years
Extended lease expiration date	May 26, 2025
Provision for lease extension periods	six one year
Notice period prior to expiration of lease	180 days
Rental escalation clause	Annual rent is increased during the initial lease term by the lesser of the increase in the Consumer Price Increase or 2.0%.