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.

+ Details

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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.

+ Details

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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.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Fair value of portfolio rated below investment grade.

+ References

No definition available.

+ Details

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- Definition

Financing Receivable, Number of Loans In Foreclosure

+ References

No definition available.

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- Definition

Financing receivable, Number of loans past due

+ References

No definition available.

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- Definition

Impaired financing receivable, number of impaired loans

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Number of partnerships represented in alternative investment portfolio.

+ References

No definition available.

+ Details

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
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Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Period Type:	instant

- Definition

Amortized cost of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
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-Paragraph 16
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-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 55
-Paragraph 80
-URI https://asc.fasb.org/extlink&oid=124267575&loc=SL82922355-210448

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- Definition

Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 15
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- Definition

Amount of credit loss expense (reversal of expense) for financing receivable.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
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-Paragraph 13
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(11))
-URI https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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Balance Type:	debit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Investments (Narrative) (Details)	3 Months Ended		12 Months Ended	15 Months Ended
Investments (Narrative) (Details)	Mar. 31, 2023 USD ($) loan item	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($) loan item	Mar. 31, 2023 USD ($) loan item
Schedule of Investments [Line Items]
Decrease in gross AFS securities unrealized gains (losses)	$ 1,900,000,000
Number of partnerships in alternative investment portfolio \| item	321		328	321
Alternative investments as a percentage of overall invested assets	2.00%		2.00%
Fair value of collateral received that we are permitted to sell or re-pledge	$ 26,000,000			$ 26,000,000
Investment commitments	2,400,000,000			2,400,000,000
Investment commitments for limited partnerships	1,700,000,000			1,700,000,000
Investment commitments for private placements	277,000,000			277,000,000
Investment commitments for mortgage loans on real estate	399,000,000			$ 399,000,000
Financing Receivable, Credit Loss, Expense (Reversal)	16,000,000	$ 1,000,000
Unfunded Loan Commitment [Member]
Schedule of Investments [Line Items]
Financing Receivable, Credit Loss, Expense (Reversal)	$ 1,000,000	0
Minimum [Member]
Schedule of Investments [Line Items]
Percentage of the fair value of securities obtained as collateral under reverse repurchase agreements.	80.00%			80.00%
Maximum [Member]
Schedule of Investments [Line Items]
Percentage of the fair value of securities obtained as collateral under reverse repurchase agreements.	95.00%			95.00%
Financial Service [Member] \| Investments [Member]
Schedule of Investments [Line Items]
Fair value	$ 20,500,000,000		$ 19,200,000,000	$ 20,500,000,000
Consumer Non-Cyclical Industry [Member] \| Investments [Member]
Schedule of Investments [Line Items]
Fair value	$ 14,900,000,000		$ 14,300,000,000	$ 14,900,000,000
Mortgage Loans On Real Estate [Member] \| Geographic Concentration [Member] \| Commercial [Member] \| California [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage	28.00%		28.00%
Mortgage Loans On Real Estate [Member] \| Geographic Concentration [Member] \| Commercial [Member] \| Texas [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage				9.00%
Mortgage Loans On Real Estate [Member] \| Geographic Concentration [Member] \| Residential [Member] \| California [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage	16.00%		17.00%
Mortgage Loans On Real Estate [Member] \| Geographic Concentration [Member] \| Residential [Member] \| Florida [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage	12.00%		12.00%
Corporate Bonds [Member]
Schedule of Investments [Line Items]
Percentage of fair value rated as investment grade	96.00%		96.00%	96.00%
Amortized cost of portfolio rated below investment grade	$ 3,300,000,000		$ 3,500,000,000	$ 3,300,000,000
Fair value of portfolio rated below investment grade	3,100,000,000		$ 3,300,000,000	3,100,000,000
Mortgage Loans On Real Estate [Member]
Schedule of Investments [Line Items]
Financing Receivable, Credit Loss, Expense (Reversal)	4,000,000	$ (18,000,000)
Mortgage Loans On Real Estate [Member] \| Commercial [Member] \| Maximum [Member]
Schedule of Investments [Line Items]
Impaired financing receivable, principal balance	$ 1,000,000			$ 1,000,000
Mortgage Loans On Real Estate [Member] \| Residential [Member]
Schedule of Investments [Line Items]
Number of loans past due \| loan	74		73	74
Financing Receivable, Number of Loans In Foreclosure \| loan	36		49	36
Financing Receivable, 90 Days or More Past Due, Still Accruing	$ 15,000,000		$ 21,000,000	$ 15,000,000
Number of impaired loans \| loan	47		37	47
Impaired financing receivable, principal balance	$ 19,000,000		$ 16,000,000	$ 19,000,000
Fixed Maturity AFS Securities [Member] \| White Chapel LLC [Member] \| Investments [Member]
Schedule of Investments [Line Items]
Fair value	$ 1,000,000,000.0			$ 1,000,000,000.0
Concentration risk, percentage	1.00%
Fixed Maturity AFS Securities [Member] \| Financial Service [Member] \| Investments [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage	15.00%		15.00%
Fixed Maturity AFS Securities [Member] \| Consumer Non-Cyclical Industry [Member] \| Investments [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage	11.00%		11.00%
Securities Investment [Member] \| White Chapel LLC [Member] \| Investments [Member]
Schedule of Investments [Line Items]
Fair value			$ 1,000,000,000.0
Securities Investment [Member] \| Fannie Mae [Member] \| Investments [Member]
Schedule of Investments [Line Items]
Fair value			$ 702,000,000
Securities Investment [Member] \| Fannie Mae [Member] \| Investments [Member] \| White Chapel LLC [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage			1.00%