v3.8.0.1

Investments (Realized Investment Gains Losses Net) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Gain (Loss) on Investments [Line Items] |  |  |
Realized investment gains (losses), net | $ 432 | $ 2,194 | $ 4,025
Fixed Maturities |  |  |
Gain (Loss) on Investments [Line Items] |  |  |
Realized investment gains (losses), net | 581 | 666 | 1,634
Equity securities |  |  |
Gain (Loss) on Investments [Line Items] |  |  |
Realized investment gains (losses), net | 1,066 | 376 | 451
Commercial mortgage and other loans |  |  |
Gain (Loss) on Investments [Line Items] |  |  |
Realized investment gains (losses), net | 70 | 55 | 37
Investment Real Estate |  |  |
Gain (Loss) on Investments [Line Items] |  |  |
Realized investment gains (losses), net | 12 | 15 | 40
Joint ventures and limited partnerships |  |  |
Gain (Loss) on Investments [Line Items] |  |  |
Realized investment gains (losses), net | (23) | (94) | (122)
Derivatives |  |  |
Gain (Loss) on Investments [Line Items] |  |  |
Realized investment gains (losses), net | (1,275) | 1,175 | 1,970
Other |  |  |
Gain (Loss) on Investments [Line Items] |  |  |
Realized investment gains (losses), net | $ 1 | $ 1 | $ 15

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- Definition The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.3(a)) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 325 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=75031664&loc=d3e22529-158502 + Details
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