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Accounting Policies - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023 | Dec. 31, 2023
Accounting Policies [Abstract] |  |  |  |  |
Operating lease liability | $ 227 |  | $ 227 |  | $ 198
Operating lease liability, current, Statement of Financial Position | Other Liabilities |  | Other Liabilities |  | Other Liabilities
Operating lease right-of-use asset | $ 206 |  | $ 206 |  | $ 176
Operating lease, right-of-use asset, Statement of Financial Position | Other Assets |  | Other Assets |  | Other Assets
Weighted average common shares adjustment related to stock-based compensation (shares) | 0 | 100,000 | 100,000 | 100,000 |
Anti-dilutive potential common shares related to stock-based compensation plans (shares) | 0 |  | 0 | 0 |
Maturities of short term investments |  |  | 3 months |  |

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- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 260 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482662/260-10-50-1 + Details
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