Equity-Based Compensation - Schedule of Restricted stock unit activity (Details)	12 Months Ended
	Sep. 30, 2021 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Weighted Average Exercise Price, Outstanding at October 1, 2020	$ 20.08
Granted, weighted average exercise price	13.78
Exercised, Weighted Average Exercise Price	13.98
Forfeited, weighted average exercise price	20.84
Weighted Average Exercise Price, Outstanding at September 30, 2021	$ 21.55
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Beginning balance, Outstanding | shares	1,123,000
Granted | shares
Exercised | shares	253,000
Forfeited | shares	68,000
Ending balance, Outstanding | shares	802,000
Weighted Average Exercise Price, Outstanding at October 1, 2020	$ 15.12
Granted, weighted average exercise price
Exercised, Weighted Average Exercise Price	17.54
Forfeited, weighted average exercise price	16.47
Weighted Average Exercise Price, Outstanding at September 30, 2021	$ 14.31
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Beginning balance, Outstanding | shares	749,000
Granted | shares	876,000
Exercised | shares	221,000
Forfeited | shares	105,000
Ending balance, Outstanding | shares	1,299,000
Weighted Average Exercise Price, Outstanding at October 1, 2020	$ 16.58
Granted, weighted average exercise price	14.28
Exercised, Weighted Average Exercise Price	16.68
Forfeited, weighted average exercise price	15.20
Weighted Average Exercise Price, Outstanding at September 30, 2021	$ 15.14