Available For Sale Securities, Weighted Average Duration Of Securities.

No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Sum of the carrying amounts as of the balance sheet date of all investments.

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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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- Definition

The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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- Definition

Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

+ References

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

The aggregate value of all restricted investments.

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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) - USD ($) $ in Millions	12 Months Ended
Investments - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Debt Securities, Available-for-sale [Line Items]
Investments	$ 18,254
Debt securities available for sale, current	2,359
Long-term investments	15,732	$ 112
Restricted investments	531
Net investment income	$ 660	21	$ 20
Certificates of Deposit
Debt Securities, Available-for-sale [Line Items]
Investments		111
Residential mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
AFS weighted average duration of securities	4 years 9 months 18 days
Commercial mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
AFS weighted average duration of securities	6 years 3 months 18 days
Other asset-backed securities
Debt Securities, Available-for-sale [Line Items]
AFS weighted average duration of securities	1 year 3 months 18 days
Debt securities
Debt Securities, Available-for-sale [Line Items]
Net investment income		$ 21	$ 20