Organization and Summary of Significant Accounting Policies - Schedule of Carrying Amounts and Classifications of Assets and Liabilities for Consolidated VIEs (Details) - USD ($) $ in Millions	Jun. 30, 2024	Sep. 30, 2023
Variable Interest Entity [Line Items]
Current assets	$ 3,999	$ 4,316
Total assets	9,095	9,424
Current liabilities	3,686	3,738
Noncurrent liabilities	3,124	3,083
VIEs
Variable Interest Entity [Line Items]
Current assets	255	265
Noncurrent assets	95	121
Total assets	350	386
Current liabilities	195	228
Noncurrent liabilities	12	13
Total liabilities	$ 207	$ 241