Stockholders' and Members' Equity, Antidilutive Securities (Details) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021
Antidilutive Securities [Abstract]
Antidilutive securities excluded from computation of diluted weighted average shares (in shares)	1,629	4,251	1,842	4,327
Restricted Stock Units [Member]
Antidilutive Securities [Abstract]
Antidilutive securities excluded from computation of diluted weighted average shares (in shares)	199	143	217	173
Common Class B [Member]
Antidilutive Securities [Abstract]
Antidilutive securities excluded from computation of diluted weighted average shares (in shares)	1,430	4,108	1,625	4,154