Consolidated Balance Sheets (Parentheticals) - USD ($) shares in Millions, $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Consolidated Balance Sheets
Fixed maturities, at amortized cost	$ 23,123	$ 21,867
Common stock, par value per share	$ 0.25	$ 0.25
Common stock shares issued	296	296
Common stock shares authorized	600	600

Amount of marketable debt securities at cost, net of adjustments, which include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments. Includes available-for sale, trading and hybrid securities.

No definition available.

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- Definition

Face amount or stated value per share of common stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

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- References

No definition available.

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