CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (USD $) In Thousands, except Share data	Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Treasury Stock, at cost [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Earnings [Member]	Stockholders' Equity, Total [Member]
Balance at Jan. 01, 2011		$ 0	$ 11	$ 456,645	$ (1,028,612)	$ (1,597)	$ 1,612,927	$ 1,039,374
Balance (in shares) at Jan. 01, 2011		0	105,682,000		23,726,000
Treasury stock retired, amount	0
Net income	109,583						109,583	109,583
Changes in net unrecognized other postretirement benefit costs, net of tax	(140)							(140)
Amortization of unrecognized losses on interest rate swaps, net of tax	2,116
Unrealized gain on hedge arrangement, net of tax								2,116
Issuance of shares upon the execise of stock options				4,487				4,487
Tax withholdings related to the exercise of stock appreciation rights	(1,612)			(1,612)				(1,612)
Issuance of shares upon the execise of stock options (in shares)			193,000
Tax benefit from share-based compensation				2,663				2,663
Issuance of restricted stock, net of forfeitures								0
Issuance of restricted stock, net of forfeitures (in shares)			4,000
Amortization of restricted stock balance				2,287				2,287
Share-based compensation				3,673				3,673
Stock issued under employee stock purchase plan				542				542
Stock issued under employee stock purchase plan (in shares)			9,000
Treasury stock purchased	269,983				(274,386)			(274,386)
Treasury stock purchased (in shares)	4,237,000				4,307,000
Cash dividends							(4,771)	(4,771)
Other				68				68
Balance at Apr. 23, 2011	883,884	0	11	468,753	(1,302,998)	379	1,717,739	883,884
Balance (in shares) at Apr. 23, 2011		0	105,888,000		28,033,000
Balance at Dec. 31, 2011	847,914	0	11	500,237	(1,644,767)	2,804	1,989,629	847,914
Balance (in shares) at Dec. 31, 2011		0	106,537,000		33,738,000
Treasury stock retired, amount	1,644,767		(4)		1,644,767		(1,644,763)	0
Net income	133,506						133,506	133,506
Changes in net unrecognized other postretirement benefit costs, net of tax	(149)							(149)
Amortization of unrecognized losses on interest rate swaps, net of tax	0
Unrealized gain on hedge arrangement, net of tax	254							254
Issuance of shares upon the execise of stock options				3,957				3,957
Tax withholdings related to the exercise of stock appreciation rights	(20,768)			(20,768)				(20,768)
Issuance of shares upon the execise of stock options (in shares)			685,000
Tax benefit from share-based compensation				17,359				17,359
Issuance of restricted stock, net of forfeitures								0
Issuance of restricted stock, net of forfeitures (in shares)			12,000
Amortization of restricted stock balance				2,370				2,370
Share-based compensation				3,220				3,220
Stock issued under employee stock purchase plan				566				566
Stock issued under employee stock purchase plan (in shares)			7,000
Treasury stock purchased					(5,174)			(5,174)
Treasury stock retired			(33,738,000)		(33,738,000)
Treasury stock purchased (in shares)	0				60,000
Cash dividends							(4,428)	(4,428)
Other				22				22
Balance at Apr. 21, 2012	$ 978,649	$ 0	$ 7	$ 506,963	$ (5,174)	$ 2,909	$ 473,944	$ 978,649
Balance (in shares) at Apr. 21, 2012		0	73,503,000		60,000