Leases - Other Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jul. 01, 2018	Jun. 30, 2019	Jul. 01, 2018
Leases [Abstract]
Gain on sale-leaseback transactions	$ 100	$ 600	$ 105
Operating cash flows from operating leases			36,006
Operating cash flows from finance leases			135
Financing cash flows from finance leases			$ 981	$ 888