Basis of Presentation, Uses of Estimates and Significant Accounting Policies (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accounts Receivable, after Allowance for Credit Loss, Current	$ 21,276	$ 17,681
Revenue, Remaining Performance Obligation, Amount	11,800
Other current receivables	17,694	12,769
Inventory, Net	$ 2,800	3,500
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities
Accounts payable and accrued liabilities	$ 31,958	27,715
Other Liabilities, Current	$ 27,072	26,281
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]: 2024-01-01
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	$ 13,500	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	$ 8,600	7,100
Pharmaceutical Manufacturer Rebates Receivable [Member]
Other current receivables	$ 11,000	$ 8,200

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Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due within one year (or the operating cycle, if longer), including liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received, taxes, interest, rent and utilities, accrued salaries and bonuses, payroll taxes and fringe benefits.

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