Derivative Instruments (Open Credit Default Swap Liabilities) (Details) $ in Millions	6 Months Ended
Jun. 30, 2022 USD ($) item
Summary Of Credit Derivatives
Maximum potential payout	$ 244
BBB+ [Member] \| Derivative Contract, Maturing 12-20-2026 [Member]
Summary Of Credit Derivatives
Maturity	Jun. 20, 2027
Number of instruments \| item	4
Maximum potential payout	$ 244

Number of credit risk derivative instruments held.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

Name:	us-gaap_NumberOfCreditRiskDerivativesHeld
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant