Consolidated Statement Of Stockholders' Equity (USD $) In Thousands, unless otherwise specified	Par Value [Member] Common Class A [Member]	Par Value [Member] Common Class B [Member]	Additional Paid-In Capital [Member]	Retained Earnings (Accumulated Deficit) [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Total
BALANCES at Dec. 28, 2008	$ 575	$ 251	$ 2,203,776	$ (1,829,717)	$ (322,312)	$ (144)	$ 52,429
Net income				50,587			50,587
Other comprehensive income (loss), net of tax:
Unamortized gain					67,539		67,539
Prior service cost/credit					368		368
Other comprehensive loss related to equity investments					(119)		(119)
Other comprehensive income (loss)							67,788
Total comprehensive income (loss)							118,375
Dividends declared ($.09 per share)				(7,474)			(7,474)
Conversion of 250,000 Class B shares to Class A shares	3	(3)
Issuance of Class A shares under stock plans	19		940				959
Stock compensation expense			2,971				2,971
Purchase of treasury stock						(9)	(9)
Tax impact from stock plans			(565)				(565)
BALANCES at Dec. 27, 2009	597	248	2,207,122	(1,786,604)	(254,524)	(153)	166,686
Net income				36,183			36,183
Other comprehensive income (loss), net of tax:
Unamortized gain					8,050		8,050
Prior service cost/credit					(640)		(640)
Other comprehensive loss related to equity investments					53		53
Other comprehensive income (loss)							7,463
Total comprehensive income (loss)							43,646
Issuance of Class A shares under stock plans	6		1,161				1,167
Stock compensation expense			4,626				4,626
Purchase of treasury stock						(379)	(379)
Tax impact from stock plans			6				6
BALANCES at Dec. 26, 2010	603	248	2,212,915	(1,750,421)	(247,061)	(532)	215,752
Net income				54,389			54,389
Other comprehensive income (loss), net of tax:
Unamortized gain					(99,447)		(99,447)
Prior service cost/credit					(640)		(640)
Other comprehensive loss related to equity investments					(506)		(506)
Other comprehensive income (loss)							(100,593)
Total comprehensive income (loss)							(46,204)
Issuance of Class A shares under stock plans	6		973				979
Stock compensation expense			5,174				5,174
Purchase of treasury stock						(613)	(613)
Tax impact from stock plans			99				99
BALANCES at Dec. 25, 2011	$ 609	$ 248	$ 2,219,161	$ (1,696,032)	$ (347,654)	$ (1,145)	$ 175,187