Restructuring Costs (Schedule of Activity in Restructuring Expense Accruals) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 27, 2020	Dec. 27, 2019
Restructuring Cost And Reserve [Line Items]
Accrual beginning balance	$ 1,584
Additions		$ 3,300
Expenditures	(1,058)
Accrual ending balance	526	1,584
Severance and Other Employee Costs [Member]
Restructuring Cost And Reserve [Line Items]
Accrual beginning balance	1,247
Expenditures	(990)
Accrual ending balance	257	1,247
Exit Closure and Consolidation of Facilities [Member]
Restructuring Cost And Reserve [Line Items]
Accrual beginning balance	337
Expenditures	(68)
Accrual ending balance	$ 269	$ 337