Fair Value Measurements - Level 2 Financial Assets and Financial Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Percentage of investments in fixed maturities and equity securities classified as Level 2	95.00%
Maximum percentage of investments classified in Level 2 representing foreign bonds priced using unadjusted broker quotes	1.00%
Other derivatives [Member] \| Fair Value Inputs Level 2 [Member]
Derivative [Line Items]
Adjustment for credit risk on derivatives assets	$ 0	$ 0
Adjustment for credit risk on derivatives liabilities	$ 0	$ 0

- Definition

Maximum percentage of Level 2 investments representing foreign bonds priced using a single unadjusted market-observable input derived by averaging multiple broker-dealer quotes.

+ References

No definition available.

+ Details

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- Definition

Percentage of investments in fixed maturities and equity securities classified in Level 2

+ References

No definition available.

+ Details

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- Definition

Amount of credit risk valuation adjustment to derivative assets to properly reflect the credit quality of the counterparties.

+ References

No definition available.

+ Details

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- Definition

Amount of credit risk valuation adjustment to derivative liabilities to properly reflect the credit quality of the entity.

+ References

No definition available.

+ Details

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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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- References

No definition available.

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- Details

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