Variable Interest Entity - Schedule of Condensed Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Sep. 30, 2023
Variable Interest Entity [Line Items]
Restricted cash and cash equivalents	$ 7,130	$ 3,844
Other current assets	526,927	292,036
Securitized intangible asset, net	90,036	92,202
Current maturities of securitized long-term debt	9,922	9,922
Securitized long-term debt	85,078	85,078
Variable Interest Entity, Primary Beneficiary | AEK
Variable Interest Entity [Line Items]
Restricted cash and cash equivalents	7,130	3,844
Other current assets	23	11
Securitized intangible asset, net	90,036	92,202
Accrued interest	2,598	1,374
Current maturities of securitized long-term debt	9,922	9,922
Securitized long-term debt	$ 85,078	$ 85,078