Segment Information (Schedule of Other Assets) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020
Segment Reporting Information [Line Items]
Cash and cash equivalents	$ 12	$ 13
Accounts receivable	708	368
Property, plant and equipment	8,002	4,111
Unamortized debt expense	34	20
Right-of-use lease assets	144	163
TOTAL ASSETS	9,241	$ 5,160	$ 4,157
Other
Segment Reporting Information [Line Items]
Cash and cash equivalents	12		95
Accounts receivable	4		7
Prepayments	13		3
Property, plant and equipment	12		18
Unamortized debt expense	10		10
Right-of-use lease assets	67		74
Non-qualified retirement plan	4		5
Long-term hedging asset (interest rate swaps)	1		0
TOTAL ASSETS	$ 123		$ 212