Income Taxes, Benefit from (provision for) income taxes (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Components of Benefit From (Provision For) Income Taxes:
Texas Margin Tax	[1]	$ (10)	$ (10)	$ (29)	$ (37)
Other		(1)	1	(4)	0
Provision for income taxes		(18)	(16)	(54)	(57)
OTA Holdings, Inc. [Member]
Components of Benefit From (Provision For) Income Taxes:
Provision for income taxes		$ (7)	$ (7)	$ (21)	$ (20)

[1] Although the Texas Margin Tax is not considered a state income tax, it has the characteristics of an income tax since it is determined by applying a tax rate to a base that considers our Texas-sourced revenues and expenses.