Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Sep. 30, 2022
Transfer from fair value level 1 to level 2	$ 0	$ 0
Transfer from fair value level 2 to level 1	0	0
Transfer into (out of) level 3	0	$ 0
2026 Notes [Member] | Notes Payable [Member] | Level 1 [Member]
Notes Payable, Fair Value Disclosure	$ 37,290