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Future Policy Benefits Reserves - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Insurance [Abstract]
Liability for future policy benefit, expected future gross premium, discounted, before reinsurance	$ 3,546	$ 3,853	$ 3,546	$ 3,853
Liability for future policy benefit, weighted-average duration	11 years	12 years	11 years	12 years
Liability future policy benefit, losses recognized in current period	$ 24	$ 29	$ 44	$ 42
Liability future policy benefit, losses recognized in prior period	$ 6	$ 1	$ 8	$ 11

X

- Definition

Liability For Future Policy Benefit, Losses Recognized In Current Period Reversed Due To Favorable Development

+ References

No definition available.

+ Details

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X

- Definition

Liability For Future Policy Benefit, Losses Recognized In Prior Period Reversed Due To Favorable Development

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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X

- Definition

Amount, before effect of reinsurance, of discounted balance for expected future gross premium component of liability for future policy benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480081/944-40-50-6

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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X

- Definition

Weighted-average duration of liability for future policy benefit, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)(5)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480081/944-40-50-6

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