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Consolidated Balance Sheet (Parenthetical) - USD ($) shares in Millions, $ in Millions | Mar. 31, 2026 | Dec. 31, 2025
--- | --- | ---
Statement of Financial Position [Abstract] |  |
Fiduciary cash | $ 7,069 | $ 7,142
Tax credit carryforwards | $ 655 | $ 713
Common stock - issued shares (in shares) | 256.9 | 257.0
Common stock - outstanding shares (in shares) | 256.9 | 257.0
Number of authorized shares not disclosed | true |

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