Financing arrangements - Schedule of Borrowings (Details) $ in Millions	Mar. 31, 2024 USD ($)	Mar. 31, 2024 EUR (€)	Mar. 31, 2024 GBP (£)	Dec. 31, 2023 USD ($)
Debt Instrument [Line Items]
Unamortized bond discounts, premiums and issuance costs, net	$ (1,404)			$ (1,420)
Fair value adjustments	(363)			(314)
Other	33			17
Total carrying value of debt	64,020			64,613
Less current portion	(3,959)			(1,443)
Total long-term debt	$ 60,061			63,170
Notes | 3.625% notes due 2024 (3.625% 2024 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	3.625%	3.625%	3.625%
Long-term debt, gross	$ 1,400			1,400
Notes | 1.90% notes due 2025 (1.90% 2025 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	1.90%	1.90%	1.90%
Long-term debt, gross	$ 500			500
Notes | 5.25% notes due 2025 (5.25% 2025 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	5.25%	5.25%	5.25%
Long-term debt, gross	$ 2,000			2,000
Notes | 3.125% notes due 2025 (3.125% 2025 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	3.125%	3.125%	3.125%
Long-term debt, gross	$ 1,000			1,000
Notes | 2.00% €750 million notes due 2026 (2.00% 2026 euro Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	2.00%	2.00%	2.00%
Face amount | €		€ 750,000,000
Long-term debt, gross	$ 809			828
Notes | 5.507% notes due 2026 (5.507% 2026 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	5.507%	5.507%	5.507%
Long-term debt, gross	$ 1,500			1,500
Notes | 2.60% notes due 2026 (2.60% 2026 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	2.60%	2.60%	2.60%
Long-term debt, gross	$ 1,250			1,250
Notes | 5.50% £475 million notes due 2026 (5.50% 2026 pound sterling Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	5.50%	5.50%	5.50%
Face amount | £			£ 475,000,000
Long-term debt, gross	$ 600			605
Notes | 2.20% notes due 2027 (2.20% 2027 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	2.20%	2.20%	2.20%
Long-term debt, gross	$ 1,724			1,724
Notes | 3.20% notes due 2027 (3.20% 2027 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	3.20%	3.20%	3.20%
Long-term debt, gross	$ 1,000			1,000
Notes | 5.15% notes due 2028 (5.15% 2028 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	5.15%	5.15%	5.15%
Long-term debt, gross	$ 3,750			3,750
Notes | 1.65% notes due 2028 (1.65% 2028 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	1.65%	1.65%	1.65%
Long-term debt, gross	$ 1,234			1,234
Notes | 3.00% notes due 2029 (3.00% 2029 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	3.00%	3.00%	3.00%
Long-term debt, gross	$ 750			750
Notes | 4.05% notes due 2029 (4.05% 2029 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	4.05%	4.05%	4.05%
Long-term debt, gross	$ 1,250			1,250
Notes | 4.00% £700 million notes due 2029 (4.00% 2029 pound sterling Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	4.00%	4.00%	4.00%
Face amount | £			£ 700,000,000
Long-term debt, gross	$ 884			892
Notes | 2.45% notes due 2030 (2.45% 2030 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	2.45%	2.45%	2.45%
Long-term debt, gross	$ 1,250			1,250
Notes | 5.25% notes due 2030 (5.25% 2030 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	5.25%	5.25%	5.25%
Long-term debt, gross	$ 2,750			2,750
Notes | 2.30% notes due 2031 (2.30% 2031 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	2.30%	2.30%	2.30%
Long-term debt, gross	$ 1,250			1,250
Notes | 2.00% notes due 2032 (2.00% 2032 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	2.00%	2.00%	2.00%
Long-term debt, gross	$ 1,001			1,001
Notes | 3.35% notes due 2032 (3.35% 2032 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	3.35%	3.35%	3.35%
Long-term debt, gross	$ 1,000			1,000
Notes | 4.20% notes due 2033 (4.20% 2033 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	4.20%	4.20%	4.20%
Long-term debt, gross	$ 750			750
Notes | 5.25% notes due 2033 (5.25% 2033 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	5.25%	5.25%	5.25%
Long-term debt, gross	$ 4,250			4,250
Notes | 6.375% notes due 2037 (6.375% 2037 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	6.375%	6.375%	6.375%
Long-term debt, gross	$ 478			478
Notes | 6.90% notes due 2038 (6.90% 2038 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	6.90%	6.90%	6.90%
Long-term debt, gross	$ 254			254
Notes | 6.40% notes due 2039 (6.40% 2039 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	6.40%	6.40%	6.40%
Long-term debt, gross	$ 333			333
Notes | 3.15% notes due 2040 (3.15% 2040 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	3.15%	3.15%	3.15%
Long-term debt, gross	$ 1,768			1,803
Notes | 5.75% notes due 2040 (5.75% 2040 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	5.75%	5.75%	5.75%
Long-term debt, gross	$ 373			373
Notes | 2.80% notes due 2041 (2.80% 2041 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	2.80%	2.80%	2.80%
Long-term debt, gross	$ 828			949
Notes | 4.95% notes due 2041 (4.95% 2041 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	4.95%	4.95%	4.95%
Long-term debt, gross	$ 600			600
Notes | 5.15% notes due 2041 (5.15% 2041 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	5.15%	5.15%	5.15%
Long-term debt, gross	$ 729			729
Notes | 5.65% notes due 2042 (5.65% 2042 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	5.65%	5.65%	5.65%
Long-term debt, gross	$ 415			415
Notes | 5.60% notes due 2043 (5.60% 2043 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	5.60%	5.60%	5.60%
Long-term debt, gross	$ 2,750			2,750
Notes | 5.375% notes due 2043 (5.375% 2043 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	5.375%	5.375%	5.375%
Long-term debt, gross	$ 185			185
Notes | 4.40% notes due 2045 (4.40% 2045 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	4.40%	4.40%	4.40%
Long-term debt, gross	$ 2,250			2,250
Notes | 4.563% notes due 2048 (4.563% 2048 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	4.563%	4.563%	4.563%
Long-term debt, gross	$ 1,415			1,415
Notes | 3.375% notes due 2050 (3.375% 2050 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	3.375%	3.375%	3.375%
Long-term debt, gross	$ 1,914			2,132
Notes | 4.663% notes due 2051 (4.663% 2051 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	4.663%	4.663%	4.663%
Long-term debt, gross	$ 3,541			3,541
Notes | 3.00% notes due 2052 (3.00% 2052 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	3.00%	3.00%	3.00%
Long-term debt, gross	$ 919			999
Notes | 4.20% notes due 2052 (4.20% 2052 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	4.20%	4.20%	4.20%
Long-term debt, gross	$ 895			950
Notes | 4.875% notes due 2053 (4.875% 2053 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	4.875%	4.875%	4.875%
Long-term debt, gross	$ 1,000			1,000
Notes | 5.65% notes due 2053 (5.65% 2053 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	5.65%	5.65%	5.65%
Long-term debt, gross	$ 4,250			4,250
Notes | 2.77% notes due 2053 (2.77% 2053 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	2.77%	2.77%	2.77%
Long-term debt, gross	$ 940			940
Notes | 4.40% notes due 2062 (4.40% 2062 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	4.40%	4.40%	4.40%
Long-term debt, gross	$ 1,165			1,200
Notes | 5.75% notes due 2063 (5.75% 2063 Notes)
Debt Instrument [Line Items]
Interest rate, stated percentage	5.75%	5.75%	5.75%
Long-term debt, gross	$ 2,750			2,750
Notes | Other notes due 2097
Debt Instrument [Line Items]
Long-term debt, gross	100			100
Secured Debt | Term Loan Due April 2025
Debt Instrument [Line Items]
Long-term debt, gross	2,000			2,000
Secured Debt | Term Loan Due October 2026
Debt Instrument [Line Items]
Long-term debt, gross	$ 2,000			$ 2,000