Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 30, 2017	Dec. 31, 2016	Dec. 26, 2015
Income Taxes [Line Items]
Federal tax rate		35.00%	35.00%	35.00%
Effective tax rate		(24.50%)	30.10%	35.70%
2017 tax reform		$ (49,336)
Effective tax rate, excluding bargain purchase gain			37.20%
Operating Loss Carryforwards		98,100
Unrecognized tax benefits that would impact effective tax rate		$ 1,567	$ 1,860	$ 1,264
Scenario, Plan [Member]
Income Taxes [Line Items]
Federal tax rate	21.00%
Earliest Tax Year [Member]
Income Taxes [Line Items]
Operating Loss Carryforwards, Expiration Date		Dec. 31, 2027
Earliest Tax Year [Member] | PENNSYLVANIA
Income Taxes [Line Items]
Open Tax Year		2014
Latest Tax Year [Member]
Income Taxes [Line Items]
Internal Revenue Service income tax examination, year		2008
Latest Tax Year [Member] | PENNSYLVANIA
Income Taxes [Line Items]
Open Tax Year		2017
Federal [Member]
Income Taxes [Line Items]
Income Taxes Paid		$ 12,000	27,300	28,000
State [Member]
Income Taxes [Line Items]
Income Taxes Paid		$ 1,000	$ 3,700	$ 2,200