Deferred Revenue (Estimated Deferred Revenue) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Fiscal year ended:
2020	$ 394
2021	50
2022	12
2023	9
2024	5
2025 and thereafter	2
Total	472	$ 274
Initial Listing Revenues
Fiscal year ended:
2020	21
2021	19
2022	11
2023	8
2024	5
2025 and thereafter	2
Total	66	69
Annual Listings Revenues
Fiscal year ended:
2020	182
2021	0
2022	0
2023	0
2024	0
2025 and thereafter	0
Total	182	2
Corporate Solutions Revenues
Fiscal year ended:
2020	40
2021	4
2022	0
2023	0
2024	0
2025 and thereafter	0
Total	44	41
Information Services Revenues
Fiscal year ended:
2020	94
2021	10
2022	0
2023	0
2024	0
2025 and thereafter	0
Total	104	82
Market Technology Revenues
Fiscal year ended:
2020	47
2021	13
2022	0
2023	0
2024	0
2025 and thereafter	0
Total	60	66
Other
Fiscal year ended:
2020	10
2021	4
2022	1
2023	1
2024	0
2025 and thereafter	0
Total	$ 16	$ 14

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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