Basis of Presentation, Uses of Estimates and Significant Accounting Policies (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Accounts Receivable, after Allowance for Credit Loss, Current	$ 22,365	$ 21,276
Revenue, Remaining Performance Obligation, Amount	12,700
Other current receivables	26,089	17,694
Inventory, Net	$ 3,800	2,800
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities
Accounts payable and accrued liabilities	$ 34,337	31,958
Other Liabilities, Current	$ 27,346	27,072
Number Of Days Notice Required To Cancel Health Insurance Contract	30 days
Goodwill, Impairment Loss	$ 0	0	$ 0
Impairment of Intangible Assets (Excluding Goodwill)	$ 0	0	$ 0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Percentage	50.00%
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	3 years
Other Current Liabilities [Member]
Health savings account deposits	$ 13,700	13,500
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Share-based Compensation Arrangement by Share-based Payment Plan Award, Options, Award Exercisable Period	10 years
Employee Stock Purchase Plan (ESPP) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Offering Date	10.00%
Health Insurance Product Line [Member]
Short-duration Insurance Contracts, Historical Claims Duration, First 90 Days	0.90
Products and services [Member]
Accounts Receivable, after Allowance for Credit Loss, Current	$ 9,900	8,600
Pharmaceutical Manufacturer Rebates Receivable [Member]
Other current receivables	$ 12,500	$ 11,000

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