Loss per Share - Schedule of Dilutive Securities (Details) - shares	3 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Class B-1 common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	51,499,195	51,499,195
Shares underlying the conversion option in the 2030 Convertible Senior Notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	18,738,880	0
Outstanding pre-IPO options issued pursuant to the 2020 Unit Option Plan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	2,928,143	4,846,089
Outstanding phantom units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	0	256,935
Restricted Stock Units (RSUs)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	2,914,001	2,351,121
Restricted Stock Units (RSUs) \| Nispera
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	177,067	354,134
Outstanding performance share units (“PSUs”)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	1,021,724	329,055
Outstanding non-qualified stock options (“NQSOs”)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	492,580	132,524