Deferred Revenue - Schedule of Deferred Revenue Estimate (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
2020	$ 129
2021	32
2022	22
2023	11
2024	6
Thereafter	1
Total	201	$ 217	$ 216
Original Listing Revenues
Disaggregation of Revenue [Line Items]
2020	15
2021	4
2022	0
2023	0
2024	0
Thereafter	0
Total	19	25	25
Other Listing Revenues
Disaggregation of Revenue [Line Items]
2020	31
2021	24
2022	21
2023	11
2024	6
Thereafter	1
Total	94	100	98
Data Services and Other Revenues
Disaggregation of Revenue [Line Items]
2020	83
2021	4
2022	1
2023	0
2024	0
Thereafter	0
Total	$ 88	$ 92	$ 93