Earnings per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Numerator:
Income from continuing operations	$ 149,943	$ 109,828	$ 424,003	$ 313,154
Loss from discontinued operations	(18)	(2)	(73)	(388)
NET INCOME	149,925	109,826	423,930	312,766
Adjustment for basic earnings per share:
Earnings allocated to unvested shareholders	(606)	(332)	(1,612)	(931)
Numerator for basic earnings per share:
From continuing operations	149,337	109,496	422,391	312,223
From discontinued operations	(18)	(2)	(73)	(388)
Net income (loss) attributable to parent, basic	149,319	109,494	422,318	311,835
Adjustment for diluted earnings per share:
Effect of reallocating undistributed earnings of unvested shareholders	7	5	22	17
Numerator for diluted earnings per share:
From continuing operations	149,344	109,501	422,413	312,240
From discontinued operations	(18)	(2)	(73)	(388)
Net income (loss) attributable to parent, diluted	$ 149,326	$ 109,499	$ 422,340	$ 311,852
Denominator:
Denominator for basic earnings per share - weighted-average shares (in shares)	107,016	106,962	107,196	106,501
Effect of dilutive shares from stock options and restricted stock (in shares)	1,409	1,822	1,602	2,049
Denominator for diluted earnings per share - adjusted weighted-average shares (in shares)	108,425	108,784	108,798	108,550
Basic earnings per common share:
Income from continuing operations (in dollars per share)	$ 1.40	$ 1.02	$ 3.94	$ 2.93
Net income (in dollars per share)	$ 1.40	$ 1.02	$ 3.94	$ 2.93
Diluted earnings per common share:
Income from continuing operations (in dollars per share)	$ 1.38	$ 1.01	$ 3.88	$ 2.87
Net income (in dollars per share)	$ 1.38	$ 1.01	$ 3.88	$ 2.87
Outstanding equity awards
Shares excluded from calculation of diluted earnings per share (in shares)	755		446	323
Weighted-average price per share (in dollars per share)	$ 54.86		$ 59.68	$ 47.94