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Equity-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions				3 Months Ended
	Nov. 18, 2021	Nov. 15, 2021	Nov. 16, 2020	Dec. 31, 2021	Dec. 31, 2020	Sep. 30, 2021	Mar. 10, 2020	Oct. 22, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted \| shares				783,000
Number of shares exercised				1,000
Equity-based compensation				$ 4.7	$ 4.9
Unrecognized compensation cost				$ 35.1	$ 40.5
Unamortized value of outstanding stock-based compensation, weighted average remaining life				1 year 10 months 24 days
Amended and Restated 2018 Omnibus Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares of common stock that may be issued							18,650,000
ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares available for sale								1,100,000
Common stock shares issued		112,000	120,000
Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issued shares of common stock				557,000		802,000
RSUs Forfeited				21,000
Restricted Stock Units (RSUs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issued shares of common stock				1,600,000		1,299,000
Vesting period				4 years
Non-cash equity-based compensation expense over the requisite service period				$ 9.4
Stock options weighted average grant date fair value				$ 15.04
Number of shares exercised				359,000
RSUs Forfeited				54,000
Common stock shares issued				714,000
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average exercise price	$ 15.04
Vesting period	4 years
Non-cash equity-based compensation expense over the requisite service period	$ 4.7
Stock options weighted average grant date fair value	$ 6.84
Number of shares exercised				1,000
Number of shares forfeited				97,000
Common stock shares issued	783,000