| **Accumulated Other Comprehensive Income (Loss) by Component (Tables)**  | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
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| **Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| Accumulated Other Comprehensive Income (Loss) by Component               | The tables below display the changes in Accumulated other comprehensive income (loss) by component for the three months ended March 31, 2014 and 2013.(In millions)Net unrealized gains (losses) on investments with OTTI losses Net unrealized gains (losses) on other investments Net unrealized gains (losses) on discontinued operations Pension and postretirement benefits Cumulative foreign currency translation adjustment TotalBalance at January 1, 2014$26 $692 $— $(426) $150 $442Transfer to net assets held for sale(5) (17) 22 — — —Other comprehensive income (loss) before reclassifications12 264 8 — (8) 276Amounts reclassified from accumulated other comprehensive income (loss) after tax (expense) benefit of $0, $(14), $0, $1, $0, and $(13)— 27 — (1) — 26Other comprehensive income (loss) after tax (expense) benefit of $(6), $(127), $(5), $(1), $0 and $(139)12 237 8 1 (8) 250Balance at March 31, 2014$33 $912 $30 $(425) $142 $692(In millions)Net unrealized gains (losses) on investments with OTTI losses Net unrealized gains (losses) on other investments Pension and postretirement benefits Cumulative foreign currency translation adjustment TotalBalance at January 1, 2013$20 $1,371 $(721) $161 $831Other comprehensive income (loss) before reclassifications14 (49) — (61) (96)Amounts reclassified from accumulated other comprehensive income (loss) after tax (expense) benefit of $0, $(6), $3, $0, and $(3)— 13 (5) — 8Other comprehensive income (loss) after tax (expense) benefit of $(7), $35, $(3), $0, and $2514 (62) 5 (61) (104)Balance at March 31, 2013$34 $1,309 $(716) $100 $727 |

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| - Definition
Tabular disclosure of the components of accumulated other comprehensive income (loss).
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=28358780&loc=SL7669686-108580
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