Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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Tax year that remains open to examination under enacted tax laws, in CCYY format.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Expiration date of each operating loss carryforward included in operating loss carryforward, in CCYY-MM-DD format.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Income Taxes [Line Items]

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Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 31, 2018	Dec. 29, 2018	Dec. 30, 2017
Income Taxes [Line Items]
Federal tax rate	21.00%	21.00%	21.00%	35.00%
Effective tax rate	23.30%		23.60%	(24.50%)
2017 tax reform			$ 657	$ (49,336)
Unrecognized tax benefits that would impact effective tax rate	$ 1,800		1,700	1,600
Earliest Tax Year [Member] \| PENNSYLVANIA
Income Taxes [Line Items]
Open Tax Year	2016
Latest Tax Year [Member] \| PENNSYLVANIA
Income Taxes [Line Items]
Open Tax Year	2019
Federal [Member]
Income Taxes [Line Items]
Income Taxes Paid	$ 11,300		4,500	12,000
State [Member]
Income Taxes [Line Items]
Income Taxes Paid	2,800		$ 2,100	$ 1,000
Operating Loss Carryforwards	$ 83,400
Operating Loss Carryforwards, Expiration Date	Jan. 01, 2027