Fair Value Measurements - Summary of Financial Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Liabilities:
Contingent consideration		$ 2,600	$ 15,300
Reported Value Measurement
Assets:
Investment in equity securities	$ 128	326
Prepaid expenses and other current assets	1,560
Liabilities:
Contingent consideration	15,161	21,181
Derivative Instruments in Hedges, Liabilities, at Fair Value	3,626
Level 1 | Reported Value Measurement
Assets:
Investment in equity securities	128	326
Prepaid expenses and other current assets	0
Liabilities:
Contingent consideration	0	0
Derivative Instruments in Hedges, Liabilities, at Fair Value	0
Level 2 | Reported Value Measurement
Assets:
Investment in equity securities	0	0
Prepaid expenses and other current assets	1,560
Liabilities:
Contingent consideration	0	0
Derivative Instruments in Hedges, Liabilities, at Fair Value	3,626
Level 3 | Reported Value Measurement
Assets:
Investment in equity securities	0	0
Prepaid expenses and other current assets	0
Liabilities:
Contingent consideration	15,161	$ 21,181
Derivative Instruments in Hedges, Liabilities, at Fair Value	$ 0