Summary of Significant Accounting Policies (Details) - USD ($) $ / shares in Units, $ in Millions |
3 Months Ended | |||
|---|---|---|---|---|
Mar. 31, 2024 |
Mar. 31, 2023 |
Dec. 31, 2023 |
Dec. 31, 2022 |
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| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | ||||
| Decrease to shareholders' equity | $ (41,350) | $ (44,518) | $ (46,244) | $ (44,688) |
| Increase to shareholders' net income | $ (277) | $ 1,267 | ||
| Increase to diluted earnings per share (in dollars per share) | $ (0.97) | $ 4.24 | ||
| Pharmacy Benefits Management Services | Guarantees | ||||
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | ||||
| Performance guarantee liability | $ 1,900 | $ 1,600 | ||
| X | ||||||||||
- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of loss contingency liability. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of equity (deficit) attributable to parent and noncontrolling interest. Excludes temporary equity. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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