Basis of Presentation and Significant Accounting Policies Supplemental Cash Flow information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022	Dec. 31, 2021
Cash and Cash Equivalents, at Carrying Value	$ 33	$ 33	$ 32
Income Taxes Paid		6	5
Restricted Cash	10	10	5	$ 14
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	309	309	39	61	$ 23
Non Cash Exchange of Puerto Rico Bonds			185
Securities acquired (transferred) in transactions related to Puerto Rico restructurings	(1)
Long-term Debt [Member]
Interest Paid, Including Capitalized Interest, Operating and Investing Activities		50	32
Variable Interest Entity, Primary Beneficiary [Member]
Restricted Cash	$ 266	$ 266	$ 2	$ 17