Leases - Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 05, 2020	Mar. 31, 2019	Dec. 29, 2019
Leases [Abstract]
Finance lease cost: Amortization of right-of-use assets	$ 300	$ 146
Finance lease cost: Interest on lease liabilities	18	8
Operating lease cost	6,222	5,671
Short-term lease cost	175	738
Variable lease cost	646	145
Total lease cost	7,361	6,708
Operating cash flows from finance leases	18	8
Operating cash flows from operating leases	5,881	5,110
Financing cash flows from finance leases	399	246
Right-of-use assets obtained in exchange for new finance lease liabilities	213	0
Right-of-use assets obtained in exchange for new operating lease liabilities	$ 977	$ 2,467
Weighted-average remaining lease term – finance leases (in years)	2 years 8 months 4 days		2 years 9 months 3 days
Weighted-average remaining lease term – operating leases (in years)	10 years 7 months 6 days		10 years 7 months 6 days
Weighted-average discount rate – finance leases (percentage)	2.19%		2.06%
Weighted-average discount rate – operating leases (percentage)	5.89%		5.86%