Alternative investments as a percentage of overall invested assets.

No definition available.

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- Definition

Amortized cost of portfolio rated below investment grade.

+ References

No definition available.

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- Definition

This item represents the change in gross unrealized holding gain or loss on available-for-sale securities that has been included in accumulated other comprehensive income, a separate component of shareholders' equity, during the period.

+ References

No definition available.

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- Definition

Percentage of the fair value of portfolio that was rated investment grade as of balance sheet date.

+ References

No definition available.

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- Definition

This item represents the percentage of the fair value of securities obtained as collateral under reverse repurchase agreements

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No definition available.

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- Definition

Fair value of portfolio rated below investment grade.

+ References

No definition available.

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- Definition

This item represents total investment commitments as of the balance sheet date for fixed maturity available-for-sale securities, limited partnerships, real estate and mortgage loans on real estate.

+ References

No definition available.

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- Definition

This item represents investment commitments as of the balance sheet date for limited partnerships.

+ References

No definition available.

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- Definition

This item represents investment commitments as of the balance sheet date for private placements.

+ References

No definition available.

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- Definition

This item represents investment commitments as of the balance sheet date for mortgage loans.

+ References

No definition available.

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- Definition

Investments

+ References

No definition available.

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- Definition

Number of partnerships represented in alternative investment portfolio.

+ References

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
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- Definition

This item represents disclosure of all significant concentrations of credit risk or market risk arising from the subject financial instrument (as defined), whether from an individual counterparty or groups of counterparties.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
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-URI https://asc.fasb.org//1943274/2147482907/825-10-50-20

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- Definition

Fair value of collateral permitted, by contact or custom, to be sold or re-pledged.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Fair value of the collateral, or portion thereof, that has been re-pledged, delivered, or otherwise used.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 30
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- Definition

Amortized cost of financing receivable modified during period for debtor experiencing financial difficulty.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
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Investments - Narrative (Details) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
Investments - Narrative (Details) $ in Millions	Sep. 30, 2024 USD ($) investment	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) investment	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($) investment
Investments [Line Items]
Increase in gross AFS securities unrealized gains (losses)			$ (1,200)
Losses from loan modifications	$ 1	$ 1	$ 3	$ 1
Number of partnerships in alternative investment portfolio \| investment	341		341		332
Alternative investments as a percentage of overall invested assets			3.00%		3.00%
Fair value of collateral received that we are permitted to sell or re-pledge	$ 25		$ 25
Fixed maturity available-for-sale securities, at fair value	84,571		84,571		$ 82,300
Investment commitments	5,000		5,000
Investment commitments for limited partnerships	3,200		3,200
Investment commitments for mortgage loans on real estate	1,500		1,500
Investment commitments for private placements	283		283
Asset Pledged as Collateral
Investments [Line Items]
Fixed maturity available-for-sale securities, at fair value	19		19
Derivative Counterparties
Investments [Line Items]
Fair value of collateral received that we are permitted to sell or re-pledge	2,300		2,300
Fair value of securities received as collateral that have been resold or repledged	$ 11		$ 11
Minimum
Investments [Line Items]
Percentage of the fair value of securities obtained as collateral under reverse repurchase agreements.	80.00%		80.00%
Maximum
Investments [Line Items]
Percentage of the fair value of securities obtained as collateral under reverse repurchase agreements.	95.00%		95.00%
Corporate bonds
Investments [Line Items]
Amortized cost of portfolio rated below investment grade	$ 2,800		$ 2,800		2,700
Fair value of portfolio rated below investment grade	$ 2,700		$ 2,700		$ 2,600
Corporate bonds \| Credit Assessment \| Reinsurer Concentration Risk
Investments [Line Items]
Percentage of fair value rated as investment grade	96.00%		96.00%		96.00%
White Chapel V LLC \| MBS
Investments [Line Items]
Fair value, concentration of risk	$ 1,500		$ 1,500		$ 1,300
White Chapel V LLC \| Investments \| Lender Concentration Risk \| MBS
Investments [Line Items]
Concentration risk			1.00%		1.00%
White Chapel LLC \| MBS
Investments [Line Items]
Fair value, concentration of risk	1,100		$ 1,100		$ 1,000
White Chapel LLC \| Investments \| Lender Concentration Risk \| MBS
Investments [Line Items]
Concentration risk			1.00%		1.00%
Financial Service \| Securities Investment
Investments [Line Items]
Fair value, concentration of risk	16,300		$ 16,300		$ 16,600
Financial Service \| Investments \| Lender Concentration Risk \| Securities Investment
Investments [Line Items]
Concentration risk			13.00%		14.00%
Consumer Non-Cyclical Industry \| Securities Investment
Investments [Line Items]
Fair value, concentration of risk	$ 11,500		$ 11,500		$ 11,300
Consumer Non-Cyclical Industry \| Investments \| Lender Concentration Risk \| Securities Investment
Investments [Line Items]
Concentration risk			9.00%		10.00%