Employee Benefit Plans (Details Textual) - USD ($)	12 Months Ended
	Dec. 26, 2019	Dec. 27, 2018	Dec. 28, 2017	Dec. 29, 2016
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Contribution Plan, Employer Matching Contribution, Percent of Match			25.00%
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent			6.00%
Employee Benefit Cost for All Plans		$ 5,117,000	$ 4,415,000	$ 3,960,000
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax		6,609,000	7,414,000
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, after Tax		(6,985,000)	(7,763,000)
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), after Tax		515,000	579,000
Defined Benefit Plan, Accumulated Benefit Obligation		30,576,000	31,769,000
Defined Benefit Plan, Actuarial (Gain) Loss		(2,633,000)	4,244,000
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, after Tax		(685,000)	(420,000)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, before Tax		(64,000)	(64,000)
Accumulated Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Tax		$ 9,556,000	12,874,000
Description Of Defined Contribution Pension And Other Postretirement Plans		The 401(k) plan provides a matching contribution equal to 100% of the first 3% of compensation and 50% of the next 2% of compensation deposited by an employee into the 401(k) plan.
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Curtailment		$ 0	$ 0	$ 251,000
Employee Benefit Plan, Prior 2017
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay			1.00%
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), after Tax		$ 376,000	$ 349,000
Forecast [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), after Tax	$ (64,000)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, after Tax	435,000
Accumulated Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Tax	$ (499,000)
Common Stock [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Description Of Defined Contribution Pension And Other Postretirement Plans		During fiscal 2018, the first 2% of the matching contribution was made with the Company’s common stock. During fiscal 2017 and fiscal 2016, the 1% and the discretionary contributions were made with the Company’s common stock.