| **Shareholders' Equity And Dividend Restrictions (Tables)**                                           | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
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| **Shareholders Equity And Dividend Restrictions [Abstract]**                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| Change In AOCI Includes Changes In Unrealized Gains And Losses On Investments And Pension Obligations | The changes from the beginning of year to the end of year are the result of changes to other comprehensive income or loss (OCI). (Dollars in millions) 2014  2013  2012  Beforetax Incometax Net  Beforetax Incometax Net  Beforetax Incometax NetInvestments:                    AOCI, January 1 $2,335 $808 $1,527  $1,875 $647 $1,228  $1,489 $512 $977OCI before realized gains recognized in net income 514 181 333  537 188 349  426 149 277Realized gains recognized in net income (130) (47) (83)  (77) (27) (50)  (40) (14) (26)OCI 384 134 250  460 161 299  386 135 251AOCI, December 31 $2,719 $942 $1,777  $2,335 $808 $1,527  $1,875 $647 $1,228                     Pension Obligations:                    AOCI, January 1 $(18) $(6) $(12)  $(101) $(35) $(66)  $(88) $(31) $(57)OCI before realized losses recognized in net income (21) (7) (14)  83 29 54  (13) (4) (9)Realized losses recognized in net income 3 1 2  — — —  — — —OCI (18) (6) (12)  83 29 54  (13) (4) (9)AOCI, December 31 $(36) $(12) $(24)  $(18) $(6) $(12)  $(101) $(35) $(66)                     Life deferred acquisition costs, life policy reserves and other:                    AOCI, January 1 $(16) $(5) $(11)  $(50) $(17) $(33)  $(29) $(10) $(19)OCI before realized gains recognized in net income 7 3 4  40 14 26  (19) (7) (12)Realized gains recognized in net income (3) (1) (2)  (6) (2) (4)  (2) — (2)OCI 4 2 2  34 12 22  (21) (7) (14)AOCI, December 31 $(12) $(3) $(9)  $(16) $(5) $(11)  $(50) $(17) $(33)                     Summary of AOCI:                    AOCI, January 1 $2,301 $797 $1,504  $1,724 $595 $1,129  $1,372 $471 $901Investments OCI 384 134 250  460 161 299  386 135 251Pension obligations OCI (18) (6) (12)  83 29 54  (13) (4) (9)Life deferred acquisition costs, life policy reserves and other OCI 4 2 2  34 12 22  (21) (7) (14)Total OCI 370 130 240  577 202 375  352 124 228AOCI, December 31 $2,671 $927 $1,744  $2,301 $797 $1,504  $1,724 $595 $1,129                      |

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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=36458714&loc=SL7669686-108580
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