Consolidated Statements Of Income - USD ($) shares in Thousands, $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Revenues
Total Revenues	$ 1,337.8	$ 1,227.8	$ 4,139.6	$ 3,811.6
Expenses
Compensation and benefits	205.5	189.6	615.7	560.1
Technology	55.6	46.8	160.2	138.6
Professional fees and outside services	32.2	35.1	108.3	98.9
Amortization of purchased intangibles	57.2	55.5	171.0	171.0
Depreciation and amortization	31.1	34.5	95.3	101.0
Licensing and other fee agreements	79.5	83.6	242.4	247.6
Other	56.5	43.9	174.2	146.8
Total Expenses	517.6	489.0	1,567.1	1,464.0
Operating Income	820.2	738.8	2,572.5	2,347.6
Non-Operating Income (Expense)
Investment income	1,272.5	686.2	4,198.4	1,046.2
Interest and other borrowing costs	(39.6)	(40.4)	(119.7)	(122.8)
Equity in net earnings of unconsolidated subsidiaries	76.8	76.5	230.1	237.1
Other non-operating income (expense)	(1,155.6)	(581.1)	(3,733.7)	(845.1)
Total Non-Operating Income (Expense)	154.1	141.2	575.1	315.4
Income before Income Taxes	974.3	880.0	3,147.6	2,663.0
Income tax provision	224.1	200.4	736.0	609.9
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	(750.2)	(679.6)	(2,411.6)	(2,053.1)
Net Income Attributable to Common Shareholders of CME Group	$ 740.8	$ 671.1	$ 2,381.3	$ 2,027.2
Earnings per Share Attributable to Common Shareholders of CME Group:
Basic (in dollars per share)	$ 2.06	$ 1.87	$ 6.63	$ 5.65
Diluted (in dollars per share)	$ 2.06	$ 1.87	$ 6.62	$ 5.64
Weighted Average Number of Common Shares:
Basic (in shares)	359,020	358,715	358,965	358,655
Diluted (in shares)	359,619	359,288	359,448	359,206
Clearing and transaction fees [Member]
Revenues
Total Revenues	$ 1,085.5	$ 998.6	$ 3,404.0	$ 3,161.3
Market data and information services
Revenues
Total Revenues	167.6	154.3	496.5	457.7
Other
Revenues
Total Revenues	$ 84.7	$ 74.9	$ 239.1	$ 192.6

LicensingFees

No definition available.

Name:	cme_LicensingFees
Namespace Prefix:	cme_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.