Commitments And Contingencies (Details)	3 Months Ended	9 Months Ended
	Sep. 29, 2019 USD ($)	Sep. 29, 2019 USD ($)
Guarantor Obligations [Line Items]
Maximum potential future undiscounted rental payments	$ 12,600,000	$ 12,600,000
Guarantor Obligations, Operating Lease, Liability	200,000	200,000
Guarantor Obligations, Payments Made	0
Guarantor Obligations, Expected Future Payments		0
Guarantor Obligations, Current Carrying Value	$ 12,400,000	$ 12,400,000
Property Lease Guarantee [Member]
Guarantor Obligations [Line Items]
Property leases	27	27
Property leases, still in operation	1	1
Primary Lessee [Member]
Guarantor Obligations [Line Items]
Property leases	5	5