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

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- Definition Amount of noncash consideration received for selling an asset or business through a noncash (or part noncash) transaction. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 8A -URI http://asc.fasb.org/extlink&oid=82896770&loc=SL6284422-111562 + Details
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- Definition The cash inflow associated with maturities (principal being due), prepayments and calls (requests of early payments) on securities not classified as either held-to-maturity securities or trading securities which are classified as available-for-sale securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a),(b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26853-111562 + Details
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