Revenue Recognition - Schedule of Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Disaggregation of Revenue [Line Items]
Total revenues	$ 3,033	$ 2,429	$ 8,731	$ 7,237
Transaction-based expenses	684	426	1,775	1,450
Total revenues, less transaction-based expenses	2,349	2,003	6,956	5,787
Data services revenues
Disaggregation of Revenue [Line Items]
Total revenues	242	236	717	699
Services transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenues, less transaction-based expenses	994	845	2,925	2,485
Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenues, less transaction-based expenses	1,355	1,158	4,031	3,302
Exchanges Segment
Disaggregation of Revenue [Line Items]
Total revenues	1,938	1,540	5,498	4,754
Transaction-based expenses	684	426	1,775	1,450
Total revenues, less transaction-based expenses	1,254	1,114	3,723	3,304
Exchanges Segment | Data services revenues
Disaggregation of Revenue [Line Items]
Total revenues	242	236	717	699
Exchanges Segment | Net Interest Income
Disaggregation of Revenue [Line Items]
Total revenues		20		64
Revenue related to net interest income earned	27		74
Exchanges Segment | Services transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenues, less transaction-based expenses	762	639	2,261	1,902
Exchanges Segment | Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenues, less transaction-based expenses	492	475	1,462	1,402
Exchanges Segment | Services transferred over time | Data services revenues
Disaggregation of Revenue [Line Items]
Total revenues, less transaction-based expenses	242	236	717	699
Exchanges Segment | Services transferred over time | Services transferred over time related to risk management of open interest performance obligations
Disaggregation of Revenue [Line Items]
Total revenues, less transaction-based expenses	94	78	281	229
Exchanges Segment | Services transferred over time | Services transferred over time related to listings
Disaggregation of Revenue [Line Items]
Total revenues, less transaction-based expenses	122	124	366	376
Exchanges Segment | Services transferred over time | Services transferred over time related to regulatory fees, trading permits, and software licenses
Disaggregation of Revenue [Line Items]
Total revenues, less transaction-based expenses	34	37	98	98
Fixed Income and Data Services Segment
Disaggregation of Revenue [Line Items]
Total revenues	586	559	1,719	1,668
Transaction-based expenses	0	0	0	0
Total revenues, less transaction-based expenses	586	559	1,719	1,668
Fixed Income and Data Services Segment | Data services revenues
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Fixed Income and Data Services Segment | Net Interest Income
Disaggregation of Revenue [Line Items]
Total revenues		40		118
Revenue related to net interest income earned	33		105
Fixed Income and Data Services Segment | Services transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenues, less transaction-based expenses	114	114	326	343
Fixed Income and Data Services Segment | Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenues, less transaction-based expenses	472	445	1,393	1,325
Fixed Income and Data Services Segment | Services transferred over time | Services transferred over time related to risk management of open interest performance obligations
Disaggregation of Revenue [Line Items]
Total revenues, less transaction-based expenses	11	9	26	25
Fixed Income and Data Services Segment | Services transferred over time | Data services revenues
Disaggregation of Revenue [Line Items]
Total revenues, less transaction-based expenses	461	436	1,367	1,300
Mortgage Technology Segment
Disaggregation of Revenue [Line Items]
Total revenues	509	330	1,514	815
Transaction-based expenses	0	0	0	0
Total revenues, less transaction-based expenses	509	330	1,514	815
Mortgage Technology Segment | Data services revenues
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Mortgage Technology Segment | Services transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenues, less transaction-based expenses	118	92	338	240
Mortgage Technology Segment | Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenues, less transaction-based expenses	391	238	1,176	575
Mortgage Technology Segment | Services transferred over time | Recurring revenues
Disaggregation of Revenue [Line Items]
Total revenues, less transaction-based expenses	387	235	1,164	564
Mortgage Technology Segment | Services transferred over time | Other
Disaggregation of Revenue [Line Items]
Total revenues, less transaction-based expenses	$ 4	$ 3	$ 12	$ 11