Basis of Presentation and Significant Accounting Policies Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Taxes Paid	$ 15	$ 11	$ 21
Cash and cash equivalents	17	20	24
Restricted Cash	5	13	55
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	23	35	81	$ 83
Reduction in Long-term Debt Through Long-term Debt Exchange	71
Long-term Debt [Member]
Interest Paid, Including Capitalized Interest, Operating and Investing Activities	80	107	143
Variable Interest Entity, Primary Beneficiary [Member]
Restricted Cash	$ 2	$ 2	$ 2