Leases - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 27, 2020	Sep. 29, 2019
Leases
Operating cash flows from finance leases	$ 435	$ 108
Financing cash flows from finance leases	1,438	371
Operating cash flows from operating leases	27,965	30,342
Right-of-use assets obtained in exchange for new finance lease liabilities	1,056	10,203
Right-of-use assets obtained in exchange for new operating lease liabilities	18,421	13,335
Cash received from sublease income	$ 7,641	$ 7,196