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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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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Amount, before allocation of a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards.

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