Investments Recorded At Fair Value That Carry Rating Of A A Plus, Weighted Average, Duration

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- Definition

Positions from which gross unrealized losses were generated

+ References

No definition available.

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- Definition

Total Unrealized Investment Positions

+ References

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

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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.

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- Definition

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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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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- Definition

Number of new stock issued during the period.

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- Definition

Value of shares of stock issued during the period as part of a transaction to acquire assets that do not qualify as a business combination.

+ References

No definition available.

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Short-term and Long-term Investments, Restricted Deposits - Narrative (Details) shares in Thousands, $ in Millions	1 Months Ended	12 Months Ended
	Jan. 31, 2016 USD ($) shares	Dec. 31, 2017 USD ($) position	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Percentage of voting interests acquired	19.00%
Stock issued, shares (in shares) \| shares	1,144
Stock issued, value \| $	$ 68
Positions from which gross unrealized losses were generated \| position		1,979
Total number of positions \| position		3,475
Income from equity method investments \| $		$ 3	$ 5	$ 8
Commercial mortgage- backed securities
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Investments that carry rating of A A plus, weighted average, duration		4 years
External Credit Rating, Investment Grade \| Rated Securities
Schedule Of Investments And Restricted Deposits By Type [Line Items]
Percentage of investment grade investments rated by nationally recognized statistical rating organizations		96.00%