Stockholders' Equity (Stock Options Vested, or Expected to Vest and Exercisable) (Details) - Stock Options [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	9 Months Ended
	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options outstanding, Number of options	2,356	2,956	3,578
Options vested and exercisable, Number of options	1,876
Options vested and expected to vest, Number of options	2,342
Options outstanding, Weighted-Average Exercise Price	$ 90.78	$ 89.2	$ 86.03
Options vested and exercisable, Weighted-Average Exercise Price Per Share	86.27
Options vested and expected to vest, Weighted-Average Exercise Price Per Share	$ 90.53
Options outstanding, Weighted-Average Remaining Life in Years	5 years 2 months 12 days
Options vested and exercisable, Weighted-Average Remaining Life in Years	4 years 7 months 6 days
Options vested and expected to vest, Weighted-Average Remaining Life in Years	5 years 2 months 12 days
Options outstanding, Aggregate Intrinsic Value	$ 363,525
Options vested and exercisable, Aggregate Intrinsic Value	297,983
Options vested and expected to vest, Aggregate Intrinsic Value	$ 361,901