Consolidated Statements of Stockholders' Equity (Deficit) (USD $) In Thousands, unless otherwise specified	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Treasury Stock	Accumulated Other Comprehensive Loss
Balance at Sep. 30, 2010	$ (461,272)	$ 1,822	$ 650,315	$ (1,093,030)	$ (103)	$ (20,276)
Balance (in shares) at Sep. 30, 2010		182,230
Increase (Decrease) in Stockholders' Equity
Net earnings	213,725			213,725
Other comprehensive income (loss)	(2,395)					(2,395)
Stock options subject to redemption	946		946
Share-based compensation	15,560	1	15,559
Share-based compensation (in shares)		96
Stock issued for stock options	14,454	18	14,436
Stock issued for stock options (in shares)		1,731
Balance at Sep. 30, 2011	(218,982)	1,841	681,256	(879,305)	(103)	(22,671)
Balance (in shares) at Sep. 30, 2011	184,057	184,057
Increase (Decrease) in Stockholders' Equity
Net earnings	233,064			233,064
Other comprehensive income (loss)	12,018					12,018
Repurchases and cancellations of common stock	(200,000)	(76)	(200,027)		103
Repurchase and cancellations of common stock (in shares)		(7,567)
Share-based compensation	16,852	1	16,851
Share-based compensation (in shares)		126
Stock issued for stock options	41,963	36	41,927
Stock issued for stock options (in shares)		3,625
Balance at Sep. 30, 2012	(115,085)	1,802	540,007	(646,241)		(10,653)
Balance (in shares) at Sep. 30, 2012	180,241	180,241
Increase (Decrease) in Stockholders' Equity
Net earnings	261,151			261,151
Other comprehensive income (loss)	835					835
Repurchases and cancellations of common stock	(509,704)	(189)	(508,278)		(1,237)
Repurchase and cancellations of common stock (in shares)		(18,894)
Share-based compensation	19,201	1	19,200
Share-based compensation (in shares)		126
Stock issued for stock options	40,123	30	40,093
Stock issued for stock options (in shares)		2,952
Balance at Sep. 30, 2013	$ (303,479)	$ 1,644	$ 91,022	$ (385,090)	$ (1,237)	$ (9,818)
Balance (in shares) at Sep. 30, 2013	164,425	164,425