Equity Incentive Plans - Schedule of Restricted Stock Unit Activity (Details) - Restricted Stock Units $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Sep. 30, 2025 USD ($) $ / shares shares
Shares
Balance of outstanding restricted stock units, beginning, Shares | shares	2,064
Granted, shares | shares	1,232	[1]
Vested, Shares | shares	(1,300)
Forfeited or not earned, Shares | shares	(100)
Balance of outstanding restricted stock units, ending, Shares | shares	1,896
Weighted- Average Grant Date Fair Value
Balance of outstanding restricted stock units, beginning (in USD per share) | $ / shares	$ 147.92
Granted (in USD per share) | $ / shares	186.37	[1]
Vested (in USD per share) | $ / shares	148.03
Forfeited or not earned (in USD per share) | $ / shares	152.65
Balance of outstanding restricted stock units, ending (in USD per share) | $ / shares	$ 173.53
Intrinsic value [Abstract]
Aggregate Intrinsic Value, Ending Balance of outstanding restricted stock | $	$ 384,917

[1] RSUs granted include 17 shares from prior period rTSR awards that were earned upon achievement of the performance criteria and vested in November 2024 and 10 shares from prior period performance-based awards that were earned upon achievement of the performance criteria and vested in November 2024.