Basis of Presentation and Significant Accounting Policies Supplemental Cash Flow information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022	Dec. 31, 2021
Cash and Cash Equivalents, at Carrying Value	$ 32	$ 32	$ 29
Income Taxes Paid		9	6
Restricted Cash	13	13	6	$ 14
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	302	302	38	61	$ 23
Non Cash Exchange of Puerto Rico Bonds			185
Securities acquired (transferred) in transactions related to Puerto Rico restructurings	(1)
VIE long-term debt issued related to Puerto Rico restructurings		133
Reduction in VIE Long-term DEbt Due to Deconsolidation		133
Long-term Debt [Member]
Interest Paid, Including Capitalized Interest, Operating and Investing Activities		50	51
Variable Interest Entity, Primary Beneficiary [Member]
Restricted Cash	$ 256	$ 256	$ 2	$ 17