Derivatives (Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 26, 2020	Dec. 28, 2019	Dec. 29, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gain (loss) on interest rate swaps		$ (1,316)	$ (1,109)	$ 531
Effective September 1, 2015 through September 1, 2021 [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional Amount		25,000
Effective September 1, 2016 through September 1, 2021 [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional Amount		25,000
Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Payments for Other Fees		1,427
Interest Rate Swap [Member] | November 7, 2014 through November 7, 2024 [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional Amount	[1]	5,796
Not Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Other Nonoperating Income (Expense)
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Reclassification Of Gain (Loss) On Dedesignation Of Derivatives, Net	[2]	861	0	0
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gain (loss) on interest rate swaps		(1,316)	(1,109)	531
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion	[3],[4]	1,106	(454)	(673)
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net		$ 135
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Other Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Cash Flow Hedge Ineffectiveness			$ 0	$ 0

[1] Interest rate swap notional amount amortizes by $35 monthly to maturity.

[2] The amount of gain (loss) recognized in income on the dedesignated portion of interest rate swaps is included in other income or other expense on the Company's Consolidated Statements of Operations. The amount of expense recognized on the Company's Consolidated Statements of Operations for the terminated portion of interest rate swaps is included in interest expense.

[3] The amount of gain (loss) reclassified from AOCIL is included in interest expense on the Company's Consolidated Statements of Operations.

[4] The amount of loss expected to be reclassified from AOCIL into earnings during the next 12 months subsequent to fiscal 2020 is $135.(3)The amount of gain (loss) recognized in income on the dedesignated portion of interest rate swaps is included in other income or other expense on the Company's Consolidated Statements of Operations. The amount of expense recognized on the Company's Consolidated Statements of Operations for the terminated portion of interest rate swaps is included in interest expense.