Fair Value Measurements (Schedule of Assets and Liabilities at Fair Value, Recurring) (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Jun. 27, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held in rabbi trusts	$ 5,047	$ 5,169
Level 1 Inputs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held in rabbi trusts	99	53
Level 2 Inputs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held in rabbi trusts	4,948	5,116
Level 3 Inputs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held in rabbi trusts	$ 0	$ 0