v3.25.3

Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2025	Dec. 31, 2024
Statement of Financial Position [Abstract]
Common stock, par value	$ 0.625
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares issued	69,304,151	69,075,329
Common stock, shares outstanding	35,678,804	35,575,691
Treasury stock, shares issued	33,625,347	33,499,638

Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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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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Number of previously issued common shares repurchased by the issuing entity and held in treasury.

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GATX CORP 10-Q