CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $) In Thousands, unless otherwise specified	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interests [Member]
Balance at Dec. 25, 2011	$ 558,430	$ 2,143	$ 1,443,484	$ (843,945)	$ (46,070)	$ 2,818
Balance, shares at Dec. 25, 2011		214,282
Comprehensive income:
Net income (loss)	151,692			151,462		230
Other comprehensive income (loss), net of tax:
Net unrealized holding losses on available-for-sale securities, net of tax	(12)				(12)
Gains (losses) associated with pension and other postretirement benefit obligations, net of tax of $0	(16,140)				(16,140)
Total other comprehensive income (loss), net of tax	(16,152)
Comprehensive income	135,540
Issuance of common stock	198,281	444	197,837
Issuance of common stock (in shares)		44,444
Share-based compensation plans:
Common stock issued under compensation plans	3	3
Common stock issued under compensation plans (in shares)		273
Requisite service period recognition	462		462
Balance at Sep. 23, 2012	892,716	2,590	1,641,783	(692,483)	(62,222)	3,048
Balance, shares at Sep. 23, 2012		258,999
Balance at Dec. 30, 2012	908,997	2,590	1,642,003	(669,711)	(68,511)	2,626
Balance, shares at Dec. 30, 2012		258,999
Comprehensive income:
Net income (loss)	406,043			406,204		(161)
Other comprehensive income (loss), net of tax:
Net unrealized holding losses on available-for-sale securities, net of tax
Gains (losses) associated with pension and other postretirement benefit obligations, net of tax of $0	36,114				36,114
Total other comprehensive income (loss), net of tax	36,114
Comprehensive income	442,157
Share-based compensation plans:
Common stock issued under compensation plans
Common stock issued under compensation plans (in shares)		30
Requisite service period recognition	2,415		2,415
Balance at Sep. 29, 2013	$ 1,353,569	$ 2,590	$ 1,644,418	$ (263,507)	$ (32,397)	$ 2,465
Balance, shares at Sep. 29, 2013		259,029