Debt - Additional Information (Details) - USD ($) $ in Thousands			12 Months Ended
	Jul. 01, 2019	Feb. 15, 2019	Sep. 30, 2020	Sep. 30, 2019	Oct. 04, 2017
Debt Instrument [Line Items]
Deferred financing costs			$ 412
Deferred financing costs amortization			200	$ 1,100
Senior Secured Term Loan Facility | Secured Debt
Debt Instrument [Line Items]
Deferred financing costs			$ 400
Weighted average interest rate (as a percent)			4.10%
Interest expense			$ 2,400
Deferred financing costs amortization			$ 200
Interest rate above applicable rate (as a percent)					2.00%
Debt extinguished	$ 147,000
Senior Secured Incremental Term Loan Facility | Secured Debt
Debt Instrument [Line Items]
Debt extinguished	$ 348,300	$ 340,100