v3.8.0.1

Investments (Fixed Maturities and Equity Securities Proceeds) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Trading Securities and Other Trading Assets [Line Items]
Proceeds from maturities/prepayments	$ 58,244	$ 49,713	$ 47,080
Proceeds from sales	4,550	3,502	4,577
Proceeds from maturities/prepayments	155	271	235
Fixed maturities | Available-for-sale
Schedule of Trading Securities and Other Trading Assets [Line Items]
Proceeds from sales	34,002	29,878	27,679
Proceeds from maturities/prepayments	24,460	19,710	19,559
Gross investment gains from sales and maturities	1,548	1,433	2,115
Gross investment losses from sales and maturities	(700)	(545)	(340)
OTTI recognized in earnings	(267)	(222)	(141)
Noncash Part Noncash Divestiture, Amount of Consideration Received	218	(125)	158
Fixed maturities | Held-to-maturity
Schedule of Trading Securities and Other Trading Assets [Line Items]
Proceeds from maturities/prepayments	153	272	235
Noncash Part Noncash Divestiture, Amount of Consideration Received	(2)	1	1
Equity securities | Available-for-sale
Schedule of Trading Securities and Other Trading Assets [Line Items]
Proceeds from sales	4,552	3,504	4,589
Gross investment gains from sales and maturities	1,187	608	746
Gross investment losses from sales and maturities	(94)	(158)	(169)
OTTI recognized in earnings	(27)	(74)	(126)
Noncash Part Noncash Divestiture, Amount of Consideration Received	$ 2	$ 2	$ 12

X

- Definition

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
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+ References

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The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis.

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The cash inflow associated with the maturity, prepayments and calls (requests for early payments) of debt securities designated as held-to-maturity.

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