Employee Benefit Plans (Benefits Expected to be Paid in Future Years) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 26, 2018	Dec. 27, 2017
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 195	$ 286
Estimated employer contributions during 2019	600
Benefits expected to be paid:
2019	584
2020	263
2021	236
2022	300
2023	393
2024 through 2028	$ 724

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

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