Commitments and Contingencies - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 28, 2018	Dec. 29, 2017	Dec. 30, 2016
Commitments And Contingencies Disclosure [Line Items]
Operating Leases, Rent Expense	$ 7,488,000	$ 6,712,000	$ 6,478,000
Purchase Obligation	12,315,000
Construction of Office and Laboratory [Member]
Commitments And Contingencies Disclosure [Line Items]
Contractual Obligation	$ 11,769,000