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Fair Value Measurements - Narrative (Details) $ in Millions, € in Billions	3 Months Ended
	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2024 USD ($)	May 08, 2024 EUR (€)
Derivative [Line Items]
Denominated debt issued \| €				€ 4.8
Accumulated other comprehensive loss	$ 989		$ 857
Carrying Amount \| Level 3 \| Variable Interest Entity, Primary Beneficiary \| Factoring and EIP Securitization Arrangement
Derivative [Line Items]
Carrying amounts of deferred purchase price assets	140		148
Interest Expense
Derivative [Line Items]
Amount amortized from AOCI into interest expense	62	$ 57
Amount expected to be amortized from AOCI into interest expense over next 12 months	259
Cross-Currency Swap
Derivative [Line Items]
Amount amortized from AOCI into interest expense	(218)
Interest Rate Contract
Derivative [Line Items]
Accumulated other comprehensive loss	$ 914		$ 960