Financial Instruments (Narrative) (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Unsecured debt \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unsecured notes	$ 375	$ 375
Private Equity Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unfunded commitments to VIEs	$ 10	$ 32

Face (par) amount of debt instrument at time of issuance.

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Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant