Leases (Supplemental Cash Flow Information) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 29, 2020	Mar. 31, 2019
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows relating to operating leases	$ 3,074	$ 3,038
Lease liabilities arising from obtaining right-of-use assets:
Operating leases	$ 1,295	$ 577