STOCKHOLDERS' EQUITY (Schedule of Changes in Unrealized Actuarial Losses) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 29, 2013	Dec. 30, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning of period	$ (68,511)
Other comprehensive income (loss) before reclassifications	21,775
Amounts reclassified from accumulated other comprehensive loss to net income	1,001
Net current year other comprehensive income (loss)	36,550	(22,441)
Balance, end of period	(45,735)	(68,511)
Pension and Other Postretirement Plans Costs [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning of period	(68,511)	(46,070)
Other comprehensive income (loss) before reclassifications	21,713	(22,886)
Amounts reclassified from accumulated other comprehensive loss to net income	1,001	445
Net current year other comprehensive income (loss)	22,714	(22,441)
Balance, end of period	(45,797)	(68,511)
Available-for-sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning of period
Other comprehensive income (loss) before reclassifications	62
Amounts reclassified from accumulated other comprehensive loss to net income
Net current year other comprehensive income (loss)	62
Balance, end of period	$ 62