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Financial Instruments - Narrative (Details) € in Millions, £ in Millions, $ in Millions	6 Months Ended
	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 GBP (£)	Jun. 30, 2023 EUR (€)	Dec. 31, 2022 USD ($)	Dec. 31, 2022 GBP (£)	Dec. 31, 2022 EUR (€)
Derivative [Line Items]
(Paid) received net proceeds from settlement of existing cross-currency interest rate swaps	$ 17	$ (645)
Net investment hedges \| Senior Euro Notes Maturing 2022 to 2039 and ECP Notes \| Senior notes
Derivative [Line Items]
Notional amount \| €				€ 7,100			€ 7,646
Net investment hedges \| Sterling senior notes due 2022 to 2031 \| Senior notes
Derivative [Line Items]
Notional amount \| £						£ 726
Interest rate swap
Derivative [Line Items]
(Paid) received net proceeds from settlement of existing cross-currency interest rate swaps	(17)	$ 645
Interest rate swap \| Fair value hedging
Derivative [Line Items]
Notional amount	1,854		£ 925	500	$ 1,854	925	500
Derivative liability fair value	616				578
Interest rate swap \| Net investment hedges
Derivative [Line Items]
Derivative liability fair value	(150)				(72)
Derivative asset fair value	178				$ 336
Currency swap \| Fair value hedging
Derivative [Line Items]
Notional amount \| £			925
Derivative liability fair value	$ 2
Currency swap \| Net investment hedges
Derivative [Line Items]
Notional amount			£ 2,380	€ 6,343		£ 2,580	€ 6,343