Related Party Transactions - Schedule of Condensed Combined Statement of Operations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Related Party Transactions [Abstract]
Allocated operating expenses	$ 18	$ 15	$ 17
Insurance Expense, Related Parties	18	15	8
Other Operating Expenses, Related Parties	23	24	21
Operations and maintenance – related parties	59	54	46
Allocated general corporate expenses	28	33	26
Management Agreement fee	9	9	8
Omnibus Agreement fee	11	9	9
Other	1	1	5
General and administrative – related parties	$ 49	$ 52	$ 48