Revenue Unpaid Incentives (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Sep. 30, 2022
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Paid Economic Incentives	$ 84	$ 81	$ 248	$ 249
Unpaid Economic Incentives	$ (192)		$ (192)		$ (187)

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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