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Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Millions, $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Statement of Financial Position [Abstract] |  |
Debt Securities, Available-for-sale, Amortized Cost | $ 17,847 | $ 16,735
Equity Securities, FV-NI, Cost | 4,154 | 3,953
Short-term investments, available-for-sale, amortized cost basis | 149 | 298
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment | $ 361 | $ 347
Common Stock, Par or Stated Value Per Share (in dollars per share) | $ 2 | $ 2
Common Stock, Shares Authorized (in shares) | 500.0 | 500.0
Common Stock, Shares, Issued (in shares) | 198.3 | 198.3
Treasury Stock, Common, Shares (in shares) | 42.3 | 41.9

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