v3.8.0.1

Investments (Net Investment Income) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |  |
Gross Investment Income | $ 17,198 | $ 16,226 | $ 15,738
Less: investment expenses | (763) | (706) | (909)
Net investment income | 16,435 | 15,520 | 14,829
Trading account assets |  |  |
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |  |
Gross Investment Income | 920 | 986 | 1,205
Commercial mortgage and other loans |  |  |
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |  |
Gross Investment Income | 2,267 | 2,243 | 2,255
Policy loans |  |  |
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |  |
Gross Investment Income | 617 | 627 | 619
Short-term investments and cash equivalents |  |  |
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |  |
Gross Investment Income | 203 | 145 | 56
Other long-term investments |  |  |
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |  |
Gross Investment Income | 1,117 | 731 | 717
Available-for-sale | Fixed Maturities |  |  |
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |  |
Gross Investment Income | 11,482 | 10,920 | 10,347
Available-for-sale | Equity securities |  |  |
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |  |
Gross Investment Income | 377 | 366 | 337
Held-to-maturity | Fixed Maturities |  |  |
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |  |
Gross Investment Income | $ 215 | $ 208 | $ 202

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- Definition Amount, before investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments. + 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 210.7-04.2) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 + Details
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- Definition Amount of expenses related to the generation of investment income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.9) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.2) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 + Details
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- Definition Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments. + 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(2)) -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 235 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-16(Column G)) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574960-122915 + Details
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