Stock-Based Compensation (Stock Options Vested, Or Expected to Vest and Are Exercisable) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	9 Months Ended
	Jun. 30, 2012	Mar. 31, 2012	Sep. 30, 2011
Stock-Based Compensation
Options outstanding, Number of options	4,605	4,673	4,228
Options outstanding, Weighted-Average Exercise Price	$ 21.73	$ 21.76	$ 20.12
Options outstanding, Weighted-Average Remaining Life in Years	5 years 9 months 19 days
Options outstanding, Aggregate Intrinsic Value	$ 81,663
Options vested and exercisable, Number of options	2,921
Options vested and exercisable, Weighted-Average Exercise Price Per Share	$ 18.68
Options vested and exercisable, Weighted-Average Remaining Life in Years	4 years 2 months 14 days
Options vested and exercisable, Aggregate Intrinsic Value	60,659
Options vested and expected to vest, Number of options	4,465
Options vested and expected to vest, Weighted-Average Exercise Price Per Share	$ 21.55
Options vested and to expected vest, Weighted-Average Remaining Life in Years	5 years 8 months 12 days
Options vested and expected to vest, Aggregate Intrinsic Value	$ 79,984