Lease - Lease Information (Details) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 28, 2019 USD ($)	Jun. 28, 2019 USD ($)
Leases [Abstract]
Operating lease cost	$ 2,231	$ 4,227
Variable lease cost	744	1,523
Total lease cost	2,975	5,750
Operating cash flows from operating leases	2,494	4,624
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	$ 10,305	$ 10,305
Weighted-average remaining lease term (years), Operating leases	7 years 1 month 12 days	7 years 1 month 12 days
Weighted-average discount rate, Operating leases	6.70%	6.70%