SIGNIFICANT ACCOUNTING POLICIES (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 25, 2012
Changes in accumulated other comprehensive loss
Balance at the beginning of the period	$ (481,316)
Other comprehensive income (loss) before reclassifications	(663)
Amounts reclassified from AOCI	3,375
Other comprehensive income	2,712	1,005
Balance at the end of the period	(478,604)
Minimum Pension and Post-Retirement Liability
Changes in accumulated other comprehensive loss
Balance at the beginning of the period	(473,448)
Amounts reclassified from AOCI	3,375
Other comprehensive income	3,375
Balance at the end of the period	(470,073)
Tax benefit	2,250
Other Comprehensive Loss Related to Equity Investments
Changes in accumulated other comprehensive loss
Balance at the beginning of the period	(7,868)
Other comprehensive income (loss) before reclassifications	(663)
Other comprehensive income	(663)
Balance at the end of the period	$ (8,531)