Market value of the shares an Employee Stock Purchase Plan

No definition available.

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- Definition

Number of directors

+ References

No definition available.

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- Definition

Amount authorized for purchase of share under share repurchase plan. Includes, but is not limited to, repurchase of stock and unit of ownership.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 505
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481520/505-30-50-4

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- Definition

Face amount or stated value per share of common stock.

+ References

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- Definition

Sum of the allocated, committed-to-be-released and suspense shares of the entity held by the plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 718
-SubTopic 40
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480489/718-40-50-1

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- Definition

Number of shares issued for nonredeemable preferred shares and preferred shares redeemable solely at option of issuer. Includes, but is not limited to, preferred shares issued, repurchased, and held as treasury shares. Excludes preferred shares classified as debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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Capital Stock (Narrative) (Details) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($) directors $ / shares shares	Dec. 31, 2023 $ / shares	Dec. 31, 2022 shares
Number of directors \| directors	22
Preferred Stock, Shares Issued	4,600,000
Share Repurchase Program, Authorized, Amount \| $	$ 3,000
Class A Common Stock (Shares) [Member]
Common Stock, Par or Stated Value Per Share \| $ / shares	$ 0.01	$ 0.01
Class B Common Stock (Shares)
Common Stock, Par or Stated Value Per Share \| $ / shares	$ 0.01	$ 0.01
Class B Common Stock, Class B1 [Member]
Number of directors	3
Class B Common Stock, Class B2 [Member]
Number of directors	2
Class B Common Stock, Class B3 [Member]
Number of directors	1
Class B common stock, Class B1, B2, B3 [Member]
Number of directors	6
CME Group Omnibus Stock Plan [Member]
Number of shares reserved for awards under the plan	40,200,000
Director Stock Plan; Class A Shares [Member]
Number of shares reserved for awards under the plan	725,000		625,000
Employee Stock Purchase Plan; Class A Shares [Member]
Number of shares reserved for awards under the plan	800,000		500,000
Market value of the shares an Employee Stock Purchase Plan	90.00%
Class A shares Purchased under Employee Stock Purchase Plan	510,567