Share-Based Payments - Market-Based Awards (Details) - Market Based Awards $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Sep. 30, 2023 USD ($) $ / shares shares
Share-Based Payments
Unvested at the beginning of the period (in shares) | shares	254
Granted (in shares) | shares	319
Forfeited (in shares) | shares	(29)
Unvested at the end of the period (in shares) | shares	544
Unvested at the beginning of the period (in dollars per share) | $ / shares	$ 22.72
Granted (in dollars per share) | $ / shares	12.04
Forfeited (in dollars per share) | $ / shares	16.76
Unvested at the end of the period (in dollars per share) | $ / shares	$ 16.77
Total unrecognized compensation expenses related to unvested awards | $	$ 4.8
Weighted average period for recognition of unvested awards	1 year 9 months 18 days