Stock-Based Compensation (Tables)

3 Months Ended

Dec. 31, 2021

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of stock-based compensation expense

	Three Months Ended December 31,
	2021		2020
Restricted stock units	$	7,197	$	6,144
Employee stock purchase plan		694		566
Total stock-based compensation expense	$	7,891	$	6,710

Restricted Stock Unit Activity

		Time-Based	Stock	Performance-
	Total Units	Units	Grants	Based Units
Three months ended December 31, 2021	149,348	59,776	24	89,548
Three months ended December 31, 2020	281,693	122,921	42	158,730

		Weighted
		Average
		Grant-Date
	Shares	Fair Value
Outstanding at September 30, 2021	1,088,652	$	47.35
Granted	149,348		114.42
Vested	(530,833)		37.57
Forfeited	(38,951)		59.94
Outstanding at December 31, 2021	668,216		71.19