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Financial Instruments (Narrative) (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Unsecured Notes Two | Revolving Credit Facility
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Drawn down amount under credit facility	$ 75	$ 25
Unsecured debt | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unsecured notes	375	375
Private Equity Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unfunded commitments to VIEs	$ 8	$ 9

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