Stockholders' Equity - Summary of Antidilutive Securities Excluded From Calculation (Details) - shares shares in Thousands	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Antidilutive securities excluded from computation of diluted weighted average shares (in shares)	2,037	2,032	1,746
Restricted stock units
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Antidilutive securities excluded from computation of diluted weighted average shares (in shares)	577	598	219
Employee stock purchase plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Antidilutive securities excluded from computation of diluted weighted average shares (in shares)	30	4	0
Class B Common Stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Antidilutive securities excluded from computation of diluted weighted average shares (in shares)	1,430	1,430	1,527