Revenue from Contracts with Customers - Contract Assets Rollforward (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Capitalized Cost To Fulfill Customer Contracts
Change in Capitalized Contract Costs
Balance at beginning of period	$ 424	$ 370
Additions	1,849	1,725
Amortization	(1,839)	(1,659)
Impairment	0	0
Foreign currency translation and other	16	(12)
Balance at end of period	450	424
Capitalized Cost To Obtain Customer Contracts
Change in Capitalized Contract Costs
Balance at beginning of period	207	195
Additions	63	73
Amortization	(68)	(54)
Impairment	0	0
Foreign currency translation and other	6	(7)
Balance at end of period	$ 208	$ 207