Stockholders' Equity (Stock Options Vested, or Expected to Vest and Exercisable) (Details) - Stock Options [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options outstanding, Number of options	3,578	4,842
Options vested and exercisable, Number of options	2,680
Options vested and expected to vest, Number of options	3,557
Options outstanding, Weighted-Average Exercise Price	$ 86.03	$ 80.48
Options vested and exercisable, Weighted-Average Exercise Price Per Share	82.14
Options vested and expected to vest, Weighted-Average Exercise Price Per Share	$ 85.91
Options outstanding, Weighted-Average Remaining Life in Years	5 years 3 months 18 days
Options vested and exercisable, Weighted-Average Remaining Life in Years	4 years 6 months
Options vested and expected to vest, Weighted-Average Remaining Life in Years	5 years 2 months 12 days
Options outstanding, Aggregate Intrinsic Value	$ 305,872
Options vested and exercisable, Aggregate Intrinsic Value	239,541
Options vested and expected to vest, Aggregate Intrinsic Value	$ 304,515