Derivative Instruments (Open Credit Default Swap Liabilities) (Details) $ in Millions	Mar. 31, 2022 USD ($) item
Summary Of Credit Derivatives
Number of instruments \| item	2
Fair value	$ 1
Maximum potential payout	56
Credit Default Swap Liabilities [Member]
Summary Of Credit Derivatives
Maximum potential payout	$ 56
BBB+ [Member] \| 12/20/2026 Maturity [Member] \| Credit Default Swap Liabilities [Member]
Summary Of Credit Derivatives
Number of instruments \| item	1
Maximum potential payout	$ 25
BBB+ [Member] \| 6/20/2027 Maturity [Member] \| Credit Default Swap Liabilities [Member]
Summary Of Credit Derivatives
Number of instruments \| item	1
Fair value	$ 1
Maximum potential payout	$ 31

No definition available.

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- Definition

Maximum potential amount of future undiscounted payments that could be required under the credit derivative, before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4K
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5708775-113959

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Fair value of credit risk derivative asset after deduction of credit risk derivative liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4K
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5708775-113959

+ Details

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- Definition

Number of credit risk derivative instruments held.

+ References

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 http://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 http://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

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- Details

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