Commitments and Contingencies - Facility and Equipment Leases (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 28, 2020	Jun. 30, 2019	Jun. 28, 2020		Jun. 30, 2019
Loss Contingencies [Line Items]
Operating lease expense	$ 4,324	$ 3,365	$ 8,641		$ 8,253
Sublease income (expense)	(20)	24	(55)		(310)
Rent expense	4,304	3,389	8,586		7,943
Operating cash flows for operating leases	2,341	3,558	7,919		8,068
Right-of-use assets obtained in exchange for lease obligations	$ 963	$ 13,280	$ 13,424	[1]	$ 94,805	[1]
Weighted-average remaining lease term (in years) - operating leases	6 years 6 months	7 years 9 months 18 days	6 years 6 months		7 years 9 months 18 days
Weighted-average discount rate - operating leases	9.00%	9.00%	9.00%		9.00%
Minimum
Loss Contingencies [Line Items]
Lessee, operating lease, renewal term	1 year		1 year
Maximum
Loss Contingencies [Line Items]
Lessee, operating lease, renewal term	10 years		10 years

[1] Amounts for the six months ended June 30, 2019 include the transition adjustment for the adoption of Accounting Standards Update ("ASU") No. 2016-02, Leases (Topic 842), as amended ("ASC 842") and additional Right-of-Use ("ROU") asset additions.