v3.25.4

Capital Stock (Capital stock) (Details) - shares	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Convertible Preferred Stock
Capital Unit [Line Items]
Preferred Stock, Shares Authorized	10,000,000	10,000,000
Preferred Stock, Shares Outstanding	4,584,000	4,584,000
Common Stock, Shares, Outstanding	4,584,000	4,584,000	4,584,000	4,584,000
Class A Common Stock (Shares) [Member]
Capital Unit [Line Items]
Common Stock, Shares Authorized	1,000,000,000	1,000,000,000
Common Stock, Shares, Outstanding	358,950,000	359,602,000	359,231,000	358,929,000
Class B Common Stock, Class B1 [Member]
Capital Unit [Line Items]
Common Stock, Shares, Outstanding	600	600
Class B Common Stock, Class B2 [Member]
Capital Unit [Line Items]
Common Stock, Shares, Outstanding	800	800
Class B Common Stock, Class B3 [Member]
Capital Unit [Line Items]
Common Stock, Shares, Outstanding	1,300	1,300
Class B Common Stock, Class B4 [Member]
Capital Unit [Line Items]
Common Stock, Shares, Outstanding	400	400

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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CME GROUP INC. 10-K