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.

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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

Fair value of portfolio rated below investment grade.

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No definition available.

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- Definition

Debt-service coverage ratio threshold indicating property operations do not generate enough income to cover payments.

+ References

No definition available.

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- Definition

Financing receivable, Number of loans past due

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No definition available.

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- Definition

Percentage threshold of loan-to-value ratios indicating principal is greater than collateral value.

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No definition available.

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- Definition

Impaired financing receivable, number of impaired loans

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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.

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No definition available.

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- Definition

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

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No definition available.

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- Definition

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

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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

Number of partnerships represented in alternative investment portfolio.

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No definition available.

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- Definition

This item represents the loss severity as a percentage of first lien loans that was considered as one of the potential factors in reaching a conclusion that the available-for-sale investments are other than temporarily impaired and the amount of such impairment determined to be related to credit loss recognized in earnings.

+ References

No definition available.

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- Definition

This item represents the loss severity as a percentage of defaulted second lien loans that was considered as one of the potential factors in reaching a conclusion that the available-for-sale investments are other than temporarily impaired and the amount of such impairment determined to be related to credit loss recognized in earnings.

+ 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

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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
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- Definition

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

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- Definition

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

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- Definition

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

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

Amount before tax of other than temporary impairment (OTTI) loss on investments in available-for-sale and held-to-maturity debt securities, recognized in other comprehensive loss.

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- 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.

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Investments (Narrative) (Details) $ in Millions	3 Months Ended		12 Months Ended
Investments (Narrative) (Details) $ in Millions	Mar. 31, 2020 USD ($) item loan	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($) loan item
Schedule of Investments [Line Items]
Decrease in gross AFS securities unrealized losses	$ (2,000)
Number of partnerships in alternative investment portfolio \| item	259		256
Alternative investments as a percentage of overall invested assets	1.00%		1.00%
Portion of loss recognized in other comprehensive income		$ 13
Fair value of collateral received that we are permitted to sell or re-pledge	25
Securities that have been re-pledged	25
Investment commitments	1,600
Investment commitments for limited partnerships	1,000
Investment commitments for private placements	352
Investment commitments for mortgage loans on real estate	$ 197
Commercial [Member]
Schedule of Investments [Line Items]
Percentage threshold of loan-to-value ratios indicating principal is greater than collateral value	100.00%
Debt-service coverage ratio threshold \| item	1.0
Number of impaired loans \| loan	2		1
Commercial [Member] \| Maximum [Member]
Schedule of Investments [Line Items]
Impaired financing receivable, principal balance	$ 1		$ 1
Residential [Member]
Schedule of Investments [Line Items]
Number of loans past due \| loan	44		38
Number of impaired loans \| loan	24		4
Impaired financing receivable, principal balance	$ 6		$ 1
Federal Home Loan Mortgage Corporation [Member] \| Investments [Member]
Schedule of Investments [Line Items]
Fair value	$ 1,300		$ 1,300
Concentration risk, percentage	1.00%		1.00%
Fannie Mae [Member] \| Investments [Member]
Schedule of Investments [Line Items]
Fair value	$ 1,000		$ 1,000
Concentration risk, percentage	1.00%		1.00%
Financial Service [Member] \| Investments [Member]
Schedule of Investments [Line Items]
Fair value	$ 17,900		$ 18,200
Concentration risk, percentage	14.00%		14.00%
Consumer Non-Cyclical Industry [Member] \| Investments [Member]
Schedule of Investments [Line Items]
Fair value	$ 15,500		$ 15,400
Concentration risk, percentage	12.00%		12.00%
Mortgage Loans On Real Estate [Member] \| Geographic Concentration Risk [Member] \| Commercial [Member] \| California [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage	24.00%		24.00%
Mortgage Loans On Real Estate [Member] \| Geographic Concentration Risk [Member] \| Commercial [Member] \| Texas [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage	11.00%		11.00%
Mortgage Loans On Real Estate [Member] \| Geographic Concentration Risk [Member] \| Residential [Member] \| California [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage	34.00%		34.00%
Mortgage Loans On Real Estate [Member] \| Geographic Concentration Risk [Member] \| Residential [Member] \| Florida [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage	18.00%		20.00%
Corporate Bonds [Member]
Schedule of Investments [Line Items]
Percentage of fair value rated as investment grade	96.00%		96.00%
Amortized cost of portfolio rated below investment grade	$ 3,600		$ 3,100
Fair value of portfolio rated below investment grade	$ 3,300		$ 3,100
MBS [Member]
Schedule of Investments [Line Items]
Severity of second lien loans	100.00%
Severity of first lien loans	30.00%