Stock-Based Compensation and Equity Grants - Stock Option Activity (Details) $ / shares in Units, shares in Thousands, $ in Thousands	6 Months Ended	12 Months Ended
	Mar. 31, 2024 USD ($) $ / shares shares	Sep. 30, 2023 USD ($) $ / shares shares
Number of Shares
Options outstanding, beginning (in shares) | shares	2,278
Granted (in shares) | shares	0
Exercised (in shares) | shares	(535)
Cancelled (in shares) | shares	(25)
Options outstanding, ending (in shares) | shares	1,718	2,278
Weighted Average Exercise Price
Options outstanding, beginning (in dollars per share) | $ / shares	$ 8.40
Granted (in dollars per share) | $ / shares	0
Exercised (in dollars per share) | $ / shares	5.03
Cancelled (in dollars per share) | $ / shares	11.66
Options outstanding, ending (in dollars per share) | $ / shares	$ 9.40	$ 8.40
Weighted Average Remaining Contractual Term
Weighted Average Remaining Contractual Term	6 years	5 years 9 months 18 days
Aggregate Intrinsic Value
Aggregate Intrinsic Value | $	$ 7,450	$ 8,693
Vested and exercisable (in shares) | shares	1,458
Vested and exercisable, weighted average exercise price (in dollars per share) | $ / shares	$ 8.31
Vested and exercisable, weighted average remaining contractual term (in years)	5 years 8 months 12 days
Vested and exercisable, intrinsic value | $	$ 7,374