CONSOLIDATED STATEMENTS OF COMMON STOCK EQUITY (USD $) In Thousands, except Share data	Total	Common Stock [Member]	Premium on Common Stock [Member]	Accumulated Other Comprehensive (Loss) Income [Member]	Treasury Stock and Other [Member]	Retained Earnings [Member]
Beginning Balance at Sep. 30, 2008	$ 728,068	$ 108,599	$ 237,001	$ (2,714)	$ (65,564)	$ 450,746
Beginning Balance (shares) at Sep. 30, 2008	42,058,000
Net income	27,242					27,242
Other comprehensive (loss)	(7,338)			(7,338)
Common stock issued under stock plans (shares)	636,000
Common stock issued under stock plans	20,415	787	10,532		9,096
Tax benefits from stock plans	1,686		1,686
Cash dividend declared	(52,217)					(52,217)
Treasury stock and other (shares)	(1,108,000)
Treasury stock and other	(28,130)				(28,130)
Ending Balance at Sep. 30, 2009	689,726	109,386	249,219	(10,052)	(84,598)	425,771
Ending Balance (shares) at Sep. 30, 2009	41,586,000
Net income	117,457					117,457
Other comprehensive (loss)	(1,955)			(1,955)
Common stock issued under stock plans (shares)	289,000
Common stock issued under stock plans	7,672	327	1,602		5,743
Tax benefits from stock plans	326		326
Cash dividend declared	(56,213)					(56,213)
Treasury stock and other (shares)	(701,000)
Treasury stock and other	(31,530)				(31,530)
Ending Balance at Sep. 30, 2010	725,483	109,713	251,147	(12,007)	(110,385)	487,015
Ending Balance (shares) at Sep. 30, 2010	41,173,608
Net income	101,299					101,299
Other comprehensive (loss)	1,403			1,403
Common stock issued under stock plans (shares)	621,000
Common stock issued under stock plans	24,128	545	12,370		11,213
Tax benefits from stock plans	2,007		2,007
Cash dividend declared	(59,552)					(59,552)
Treasury stock and other (shares)	(373,000)
Treasury stock and other	(18,511)				(18,511)
Ending Balance at Sep. 30, 2011	$ 776,257	$ 110,258	$ 265,524	$ (10,604)	$ (117,683)	$ 528,762
Ending Balance (shares) at Sep. 30, 2011	41,421,786