Debt - Summary of Outstanding Debt (Details) € in Millions, SFr in Millions, $ in Millions	1 Months Ended		9 Months Ended		12 Months Ended
	Jun. 30, 2025 EUR (€)	Feb. 28, 2025 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)	Jun. 30, 2025 CHF (SFr)	Feb. 28, 2025 EUR (€)
SHORT-TERM
Commercial paper			$ 4,730		$ 3,964
Other bank borrowings (primarily non U.S.)			232		259
Total short-term debt			4,962		4,223
LONG-TERM
Carrying value of long-term debt portfolio			20,963		17,400
Less: current portion of long-term debt			(2,371)		(2,057)
Total long-term debt			18,592		15,343
Total debt			25,925		21,623
Repayments of notes			1,654	$ 973
Derivatives Designated as Hedging Instruments - Fair Value | Interest rate swaps | Designated as Hedging Instrument
LONG-TERM
Fair value increase			$ 28		32
4.700% Notes Due 2025
LONG-TERM
Interest rate			4.70%
Carrying value of long-term debt portfolio			$ 0		599
Repayments of notes		$ 600
2.65% Notes due 2025
LONG-TERM
Interest rate			2.65%
Carrying value of long-term debt portfolio			$ 0		400
Repayments of notes		$ 400
3.625% Euro denominated notes due 2025
LONG-TERM
Interest rate			3.625%
Carrying value of long-term debt portfolio			$ 0		517
Repayments of notes | €	€ 500
1.625% Euro denominated notes due 2025
LONG-TERM
Interest rate			1.625%
Carrying value of long-term debt portfolio			$ 587		517
0.00% Euro denominated notes due 2026
LONG-TERM
Interest rate			0.00%
Carrying value of long-term debt portfolio			$ 822		726
3.20% Notes due 2026
LONG-TERM
Interest rate			3.20%
Carrying value of long-term debt portfolio			$ 725		725
3.434% Notes due 2026
LONG-TERM
Interest rate			3.434%
Carrying value of long-term debt portfolio			$ 199		199
1.652% Euro denominated notes due 2027
LONG-TERM
Interest rate			1.652%
Carrying value of long-term debt portfolio			$ 95		84
0.25% Euro denominated notes due 2027
LONG-TERM
Interest rate			0.25%
Carrying value of long-term debt portfolio			$ 880		776
1.00% Euro denominated notes due 2027
LONG-TERM
Interest rate			1.00%
Carrying value of long-term debt portfolio			$ 589		519
1.00% Euro denominated notes due 2028
LONG-TERM
Interest rate			1.00%
Carrying value of long-term debt portfolio			$ 850		742
3.00% Euro denominated notes due 2028
LONG-TERM
Interest rate			3.00%
Carrying value of long-term debt portfolio			$ 819		722
3.375% Euro denominated notes due 2029
LONG-TERM
Interest rate			3.375%
Carrying value of long-term debt portfolio			$ 877		773
2.625% Euro denominated notes Due 2029
LONG-TERM
Interest rate			2.625%				2.625%
Carrying value of long-term debt portfolio			$ 993		0
Face amount of notes issued | €							€ 850
0.6150% Swiss franc denominated notes due 2029
LONG-TERM
Interest rate			0.615%			0.615%
Carrying value of long-term debt portfolio			$ 281		0
Face amount of notes issued | SFr						SFr 225
1.10% Notes due 2030
LONG-TERM
Interest rate			1.10%
Carrying value of long-term debt portfolio			$ 697		697
1.90% Euro denominated notes due 2030
LONG-TERM
Interest rate			1.90%
Carrying value of long-term debt portfolio			$ 120		106
3.375% Euro denominated notes due 2030
LONG-TERM
Interest rate			3.375%
Carrying value of long-term debt portfolio			$ 876		772
1.375% Euro denominated notes due 2031
LONG-TERM
Interest rate			1.375%
Carrying value of long-term debt portfolio			$ 883		779
3.20% Euro denominated notes due 2031
LONG-TERM
Interest rate			3.20%
Carrying value of long-term debt portfolio			$ 996		878
0.550% Euro denominated notes due 2032
LONG-TERM
Interest rate			0.55%
Carrying value of long-term debt portfolio			$ 876		772
0.375% Euro denominated notes due 2033
LONG-TERM
Interest rate			0.375%
Carrying value of long-term debt portfolio			$ 582		512
3.00% Euro denominated notes due 2033
LONG-TERM
Interest rate			3.00%				3.00%
Carrying value of long-term debt portfolio			$ 876		0
Face amount of notes issued | €							€ 750
1.0629% Swiss franc denominated notes due 2033
LONG-TERM
Interest rate			1.0629%			1.0629%
Carrying value of long-term debt portfolio			$ 343		0
Face amount of notes issued | SFr						SFr 275
3.625% Euro denominated notes due 2034
LONG-TERM
Interest rate			3.625%
Carrying value of long-term debt portfolio			$ 760		670
3.50% Euro denominated notes due 2034
LONG-TERM
Interest rate			3.50%
Carrying value of long-term debt portfolio			$ 873		769
1.625% Euro denominated notes due 2035
LONG-TERM
Interest rate			1.625%
Carrying value of long-term debt portfolio			$ 933		822
3.40% Euro denominated notes due 2036
LONG-TERM
Interest rate			3.40%
Carrying value of long-term debt portfolio			$ 815		718
3.25% Euro denominated notes due 2037
LONG-TERM
Interest rate			3.25%				3.25%
Carrying value of long-term debt portfolio			$ 756		0
Face amount of notes issued | €							€ 650
3.55% Notes due 2042
LONG-TERM
Interest rate			3.55%
Carrying value of long-term debt portfolio			$ 666		666
3.75% Euro denominated notes due 2044
LONG-TERM
Interest rate			3.75%
Carrying value of long-term debt portfolio			$ 809		712
2.00% Notes due 2050
LONG-TERM
Interest rate			2.00%
Carrying value of long-term debt portfolio			$ 297		297
1.00% Euro denominated notes due 2051
LONG-TERM
Interest rate			1.00%
Carrying value of long-term debt portfolio			$ 804		707
Non U.S. borrowings
LONG-TERM
Carrying value of long-term debt portfolio			274		214
Other
LONG-TERM
Carrying value of long-term debt portfolio			$ 10		$ 10