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Reserves in Addition to Account Balance, Based on Expected No-Lapse Guarantee Benefits and Expected Policy Assessments (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024	Sep. 30, 2024
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	$ 3,003	$ 2,960
Life policy reserves:
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	1,628	1,554
Investment contract reserves:
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	1,375	1,406
Term Life Insurance | Life policy reserves:
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	1,099	1,051	$ 1,108
Whole Life Insurance | Life policy reserves:
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	430	405	$ 441
Long-Duration Insurance, Other | Life policy reserves:
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	99	98
Long-Duration Insurance, Other | Investment contract reserves:
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	110	109
Deferred Fixed Annuity | Investment contract reserves:
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	565	595
Universal life | Investment contract reserves:
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	588	586
Structured Settlement Annuity | Investment contract reserves:
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	$ 112	$ 116

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+ References

No definition available.

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- Definition

Amount, before effect of reinsurance, of present value of future benefit to be paid to or on behalf of policyholder and related expense less present value of future net premium receivable under insurance contract.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 605
-Name Accounting Standards Codification
-Section 55
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477548/944-605-55-14

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480081/944-40-50-6

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (g)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480016/944-40-65-2

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(13)(a)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 55
-Paragraph 29E
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480046/944-40-55-29E

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

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