Borrowings - Narrative (Details) - USD ($)						1 Months Ended
	Jul. 21, 2023	Jun. 02, 2023	May 02, 2023	May 01, 2023	Feb. 21, 2023	Feb. 28, 2023	Sep. 30, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Proceeds from debt		$ 4,900,000,000		$ 5,000,000,000	$ 6,000,000,000	$ 6,000,000,000
Senior Notes | 5% senior notes due January 2029
Debt Instrument [Line Items]
Face amount of debt		$ 1,000,000,000
Debt interest rate		5.00%					5.00%
Long-term debt							$ 1,000,000,000	$ 0
Senior Notes | 5.25% senior notes due January 2031
Debt Instrument [Line Items]
Face amount of debt		$ 750,000,000
Debt interest rate		5.25%					5.25%
Long-term debt							$ 750,000,000	0
Senior Notes | 5.3% senior notes due June 2033
Debt Instrument [Line Items]
Face amount of debt		$ 1,250,000,000
Debt interest rate		5.30%					5.30%
Long-term debt							$ 1,250,000,000	0
Senior Notes | 5.875% senior notes due June 2053
Debt Instrument [Line Items]
Face amount of debt		$ 1,250,000,000
Debt interest rate		5.875%					5.875%
Long-term debt							$ 1,250,000,000	0
Senior Notes | 6% senior notes due June 2063
Debt Instrument [Line Items]
Face amount of debt		$ 750,000,000
Debt interest rate		6.00%					6.00%
Long-term debt							$ 750,000,000	0
Senior Notes | 5% senior notes due February 2026
Debt Instrument [Line Items]
Face amount of debt					$ 1,500,000,000
Debt interest rate					5.00%		5.00%
Long-term debt							$ 1,500,000,000	0
Senior Notes | 5.125% senior notes due February 2030
Debt Instrument [Line Items]
Face amount of debt					$ 1,500,000,000
Debt interest rate					5.125%		5.125%
Long-term debt							$ 1,500,000,000	0
Senior Notes | 5.25% senior notes due February 2033
Debt Instrument [Line Items]
Face amount of debt					$ 1,750,000,000
Debt interest rate					5.25%		5.25%
Long-term debt							$ 1,750,000,000	0
Senior Notes | 5.625% senior notes due February 2053
Debt Instrument [Line Items]
Face amount of debt					$ 1,250,000,000
Debt interest rate					5.625%		5.625%
Long-term debt							$ 1,250,000,000	0
Convertible Debt | 0% convertible senior notes due March 2026
Debt Instrument [Line Items]
Debt interest rate							0.00%
Repurchase price of convertible senior notes, as a percent of principal			100.00%
Conversion of convertible senior notes with cash	$ 917,000,000
Long-term debt							$ 3,000,000	$ 0
Convertible Debt | 0% convertible senior notes due March 2026 | Oak Street Health Inc.
Debt Instrument [Line Items]
Face amount of debt				$ 920,000,000
Debt interest rate				0.00%
Loans Payable | Term Loan Agreement, 364-Day
Debt Instrument [Line Items]
Debt instrument term				364 days
Face amount of debt				$ 5,000,000,000
Proceeds from debt			$ 5,000,000,000
Debt interest rate			6.20%