Consolidated Statements Of Stockholders' Equity (USD $) In Thousands, except Share data	Class A Shares [Member]	Class A Common Stock [Member] USD ($)	Class B Common Stock [Member] USD ($)	Additional Paid-In Capital [Member] USD ($)	Accumulated Other Comprehensive Income (Loss) [Member] USD ($)	Retained Earnings [Member] USD ($)	Total USD ($)
Balance, value at Dec. 28, 2008		$ 111,251	$ 2,759	$ 21,934	$ (188,139)	$ 207,422	$ 155,227
Balance, shares at Dec. 28, 2008	22,250,130
Net loss						(35,765)	(35,765)
Unrealized gain on derivative contracts (net of deferred taxes)					8,236		8,236
Pension and postretirement (net of deferred taxes/benefit)					62,200		62,200
Comprehensive income/loss							34,671
Performance accelerated restricted stock		(276)		(333)		75	(534)
Performance accelerated restricted stock, shares	(55,253)
Stock-based compensation				2,389			2,389
Other		235		263			498
Other, shares	47,082
Balance, value at Dec. 27, 2009		111,210	2,759	24,253	(117,703)	171,732	192,251
Balance, shares at Dec. 27, 2009	22,241,959
Net loss						(22,638)	(22,638)
Unrealized gain on derivative contracts (net of deferred taxes)					7,463		7,463
Pension and postretirement (net of deferred taxes/benefit)					(16,559)		(16,559)
Comprehensive income/loss							(31,734)
Exercise of stock options		460		(262)			198
Exercise of stock options, shares	92,085
Performance accelerated restricted stock		779		(779)		34	34
Performance accelerated restricted stock, shares	155,886
Stock-based compensation				3,154			3,154
Other		20	(16)	15			19
Other, shares	3,948
Balance, value at Dec. 26, 2010		112,469	2,743	26,381	(126,799)	149,128	163,922
Balance, shares at Dec. 26, 2010	22,493,878
Net loss						(74,322)	(74,322)
Unrealized gain on derivative contracts (net of deferred taxes)					2,228		2,228
Pension and postretirement (net of deferred taxes/benefit)					(60,545)		(60,545)
Comprehensive income/loss							(132,639)
Exercise of stock options		111		(63)			48
Exercise of stock options, shares	22,132
Issuance of stock to director upon retirement		548		94			642
Issuance of stock to director upon retirement, shares	109,602
Performance accelerated restricted stock		(389)		271		65	(53)
Performance accelerated restricted stock, shares	(77,732)
Stock-based compensation				2,117			2,117
Other		5		(89)			(84)
Other, shares	861
Balance, value at Dec. 25, 2011		$ 112,744	$ 2,743	$ 28,711	$ (185,116)	$ 74,871	$ 33,953
Balance, shares at Dec. 25, 2011	22,548,741