Consolidated Statement of Changes in Redeemable Noncontrolling Interests And Stockholders' Equity (USD $) In Thousands, except Share data, unless otherwise specified	Total	Equity Attributable to Redeemable Noncontrolling Interests	Common stock	Additional paid-in capital	Retained earnings	Accumulated other comprehensive income (loss)	ESOP unallocated Shares
Balance at Sep. 26, 2009	$ 587,350		$ 13,081	$ 441,875	$ 134,338	$ (1,870)	$ (74)
Balance (in shares) at Sep. 26, 2009			130,811,052				(38,060)
Increase (Decrease) in Stockholders' Equity
Options exercised	4,770		184	4,586
Options exercised (in shares)			1,840,661
Issuance of common stock under employee stock purchase plan	4,016		17	3,999
Issuance of common stock under employee stock purchase plan (in shares)			171,872
Allocation of ESOP shares	1,376			1,302			74
Allocation of ESOP (in shares)							38,060
Stock compensation expense	7,949			7,949
Tax benefit from equity-based compensation plans	13,877			13,877
Deferred compensation expense	161			161
Other comprehensive income, net of tax	240					240
Net income	79,506				79,506
Balance at Sep. 25, 2010	699,245		13,282	473,749	213,844	(1,630)
Balance (in shares) at Sep. 25, 2010			132,823,585
Increase (Decrease) in Stockholders' Equity
Sale of common stock for private placement	291,096		918	290,178
Sale of common stock for private placement (in shares)			9,174,991
Options exercised	11,380		284	11,096
Options exercised (in shares)			2,839,426
Issuance of common stock under employee stock purchase plan	5,948		15	5,933
Issuance of common stock under employee stock purchase plan (in shares)			148,917
Issuance of common stock for public equity offering	647,363		948	646,415
Issuance of common stock for public equity offering (in shares)			9,479,544
Stock compensation expense	10,361			10,361
Tax benefit from equity-based compensation plans	61,670			61,670
Deferred compensation expense	214			214
Purchase noncontrolling interests		19,118
Adjustment of redeemable noncontrolling interests to redemption value	(1,618)	1,618			(1,618)
Cash distributions		(1,063)
Other comprehensive income, net of tax	(12,945)	(186)				(12,945)
Net income	199,501	1,547			199,501
Balance at Sep. 24, 2011	1,912,215	21,034	15,447	1,499,616	411,727	(14,575)
Balance (in shares) at Sep. 24, 2011	154,466,463		154,466,463
Increase (Decrease) in Stockholders' Equity
Options exercised	3,394		94	3,300
Options exercised (in shares)			940,369
Issuance of common stock under employee stock purchase plan	8,698		30	8,668
Issuance of common stock under employee stock purchase plan (in shares)			301,971
Restricted stock awards and units			5	(5)
Restricted stock awards and units (in shares)			55,747
Issuance of common stock under deferred compensation plan			4	(4)
Issuance of common stock under deferred compensation plan (in shares)			37,005
Repurchase of common stock	(76,470)		(312)	(76,158)
Repurchase of common stock (in shares)			(3,120,700)
Stock compensation expense	17,868			17,868
Tax benefit from equity-based compensation plans	11,064			11,064
Deferred compensation expense	211			211
Disposition of noncontrolling interest		(10,331)
Redeemable noncontrolling interest included in other long-term liabilities		(4,708)
Adjustment of redeemable noncontrolling interests to redemption value	(3,155)	3,155			(3,155)
Cash distributions		(513)
Other comprehensive income, net of tax	24,775	455				24,775
Net income	362,628	812			362,628
Balance at Sep. 29, 2012	$ 2,261,228	$ 9,904	$ 15,268	$ 1,464,560	$ 771,200	$ 10,200
Balance (in shares) at Sep. 29, 2012	152,680,855		152,680,855