Commitments and Contingencies - Additional Information (Details) - USD ($)		3 Months Ended		6 Months Ended
	Sep. 28, 2015	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Sep. 29, 2015
Other Commitments [Line Items]
Rent expense for operating leases		$ 1,000,000	$ 1,700,000	$ 2,100,000	$ 2,400,000
Beanstock and Adaptive
Other Commitments [Line Items]
Gain contingency						$ 10,000,000
Beanstock and Adaptive | Adaptive
Other Commitments [Line Items]
Damages sought (greater than)	$ 600,000
Capital leases | Minimum
Other Commitments [Line Items]
Interest rates		3.90%		3.90%
Capital leases | Maximum
Other Commitments [Line Items]
Interest rates		7.80%		7.80%
The 401 K Retirement Plan
Other Commitments [Line Items]
Company match expense				$ 400,000	$ 300,000