Commitments and Contingencies (Details) $ in Millions		1 Months Ended		3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 18, 2022 USD ($)	Aug. 31, 2022 USD ($)	Mar. 31, 2022 USD ($)	Sep. 30, 2022 USD ($) lease	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($) lease	Sep. 30, 2021 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2012 member	Sep. 30, 2020 claim
Commitments and Contingencies Disclosure [Abstract]
Guarantor obligations, number of leases | lease				68		68
Sample size | member										200
Loss Contingencies [Line Items]
Opioid litigation charges				$ 5,220	$ 0	$ 5,704	$ 0
Federal Court in Ohio Judgment | Pending Litigation
Loss Contingencies [Line Items]
Legal settlement awarded to other party		$ 651
Legal settlement, period of payment		15 years
State of Florida Settlement
Loss Contingencies [Line Items]
Legal settlement, period of payment			18 years
Opioid litigation charges			$ 484
Liability recorded in association with legal settlement			$ 484
Radcliffe and Flaim v. Aetna Inc., et al | Pending Litigation
Loss Contingencies [Line Items]
Number of claims | claim											2
Settlement Framework | Subsequent Event
Loss Contingencies [Line Items]
Legal settlement awarded to other party	$ 5,000
Legal settlement, period of payment	10 years
Settlement Framework | Subsequent Event | States and Political Subdivisions
Loss Contingencies [Line Items]
Legal settlement awarded to other party	$ 4,900
Settlement Framework | Subsequent Event | Tribal Entities
Loss Contingencies [Line Items]
Legal settlement awarded to other party	$ 130
Settlement Framework and Other Opioid-Related Claims
Loss Contingencies [Line Items]
Opioid litigation charges				$ 5,200
Settlement Framework and Other Opioid-Related Claims | Maximum | Forecast
Loss Contingencies [Line Items]
Cash impact of litigation settlement								$ 500	$ 500