Commitments And Contingencies (Details)	3 Months Ended	6 Months Ended
	Jun. 28, 2020 USD ($)	Jun. 28, 2020 USD ($)
Guarantor Obligations [Line Items]
Maximum potential future undiscounted rental payments	$ 9,300,000	$ 9,300,000
Guarantor Obligations, Payments Made	0
Guarantor Obligations, Expected Future Payments		0
Guarantor Obligations, Current Carrying Value	$ 9,300,000	$ 9,300,000
Property Lease Guarantee [Member]
Guarantor Obligations [Line Items]
Property leases	27	27
Property leases, still in operation	1	1