Leases - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2019	Sep. 30, 2018	Sep. 29, 2019	Sep. 30, 2018	Jan. 01, 2019	Dec. 31, 2018
Leases [Abstract]
Operating Lease, Liability	$ 16,167		$ 16,167
Operating lease, right-of-use asset	15,806		15,806		$ 17,522	$ 0
Operating lease, liability, current	5,445		5,445		4,736	0
Operating lease, liability, noncurrent	10,722		10,722		$ 12,669	$ 0
Operating lease, cost	1,749		4,976
Operating lease, payments	1,708		4,778
Lease, cost	$ 22		$ 255
Operating Lease, Weighted Average Discount Rate, Percent	480.00%		480.00%
Operating Lease, Weighted Average Remaining Lease Term	3 years 7 months 6 days		3 years 7 months 6 days
Operating Lease, Lease Income	$ 76	$ 77	$ 234	$ 236