Acquisitions - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2026 USD ($) acquisition	Mar. 31, 2025 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Business Combination [Line Items]
Number of businesses acquired | acquisition	5,000,000
Total outflow in the Condensed Consolidated Statements of Cash Flows	$ 126	$ 585
Goodwill	12,592	11,475	$ 13,099	$ 11,061
Business acquisition, goodwill, expected tax deductible amount	$ 18
Acquired finite-lived intangible assets, weighted average useful life	19 years
Business combination, pro forma information, revenue of acquiree since acquisition date, actual	$ 6	28
Business combination, acquiree's earnings (loss) since acquisition date, actual	(5)	(9)
2026 acquisitions
Business Combination [Line Items]
Total outflow in the Condensed Consolidated Statements of Cash Flows	126
Intangible assets, net	2
Goodwill	43
Individually immaterial business combinations
Business Combination [Line Items]
Business combination, acquisition-related cost, expense	$ 4	$ 5