| **Accumulated Other Comprehensive Income**            | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            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| **Accumulated Other Comprehensive Income [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             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| Comprehensive Income (Loss) Note                      | Accumulated Other Comprehensive IncomeAccumulated other comprehensive income (AOCI) includes changes in unrealized gains and losses on investments, changes in pension obligations and changes in life deferred acquisition costs, life policy reserves and other as follows:(Dollars in millions) Three months ended September 30,  2016  2015  Before tax Income tax Net  Before tax Income tax NetInvestments:             AOCI, beginning of period $2,673 $925 $1,748  $2,357 $815 $1,542OCI before realized gains recognized in net income 119 41 78  (363) (126) (237)Realized gains recognized in net income (57) (20) (37)  (2) (1) (1)OCI 62 21 41  (365) (127) (238)AOCI, end of period $2,735 $946 $1,789  $1,992 $688 $1,304              Pension obligations:             AOCI, beginning of period $(40) $(13) $(27)  $(33) $(11) $(22)OCI excluding amortization recognized in net income — — —  — — —Amortization recognized in net income — — —  1 — 1OCI — — —  1 — 1AOCI, end of period $(40) $(13) $(27)  $(32) $(11) $(21)              Life deferred acquisition costs, life policy reserves and other:             AOCI, beginning of period $(10) $(3) $(7)  $(8) $(2) $(6)OCI before realized gains recognized in net income (4) (1) (3)  5 1 4Realized gains recognized in net income 1 1 —  (1) — (1)OCI (3) — (3)  4 1 3AOCI, end of period $(13) $(3) $(10)  $(4) $(1) $(3)              Summary of AOCI:             AOCI, beginning of period $2,623 $909 $1,714  $2,316 $802 $1,514Investments OCI 62 21 41  (365) (127) (238)Pension obligations OCI — — —  1 — 1Life deferred acquisition costs, life policy reserves and other OCI (3) — (3)  4 1 3Total OCI 59 21 38  (360) (126) (234)AOCI, end of period $2,682 $930 $1,752  $1,956 $676 $1,280              (Dollars in millions)Nine months ended September 30, 2016  2015 Before tax Income tax Net  Before tax Income tax NetInvestments:            AOCI, beginning of period$2,094 $722 $1,372  $2,719 $942 $1,777OCI excluding realized gains recognized in net income801 280 521  (620) (216) (404)Realized gains recognized in net income(160) (56) (104)  (107) (38) (69)OCI641 224 417  (727) (254) (473)AOCI, end of period$2,735 $946 $1,789  $1,992 $688 $1,304             Pension obligations:            AOCI, beginning of period$(42) $(14) $(28)  $(36) $(12) $(24)OCI excluding amortization recognized in net income— — —  — — —Amortization recognized in net income2 1 1  4 1 3OCI2 1 1  4 1 3AOCI, end of period$(40) $(13) $(27)  $(32) $(11) $(21)             Life deferred acquisition costs, life policy reserves and other:            AOCI, beginning of period$1 $1 $—  $(12) $(3) $(9)OCI excluding realized gains recognized in net income(13) (4) (9)  11 3 8Realized gains recognized in net income(1) — (1)  (3) (1) (2)OCI(14) (4) (10)  8 2 6AOCI, end of period$(13) $(3) $(10)  $(4) $(1) $(3)             Summary of AOCI:            AOCI, beginning of period$2,053 $709 $1,344  $2,671 $927 $1,744Investments OCI641 224 417  (727) (254) (473)Pension obligations OCI2 1 1  4 1 3Life deferred acquisition costs, life policy reserves and other OCI(14) (4) (10)  8 2 6Total OCI629 221 408  (715) (251) (464)AOCI, end of period$2,682 $930 $1,752  $1,956 $676 $1,280             Investments realized gains and life deferred acquisition costs, life policy reserves and other realized gains are recorded in the realized investment gains, net, line item in the condensed consolidated statements of income. Amortization on pension obligations is recorded in the insurance losses and contract holders' benefits and underwriting, acquisition and insurance expenses in the condensed consolidated statements of income. |

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| - Definition
Accumulated Other Comprehensive Income [Abstract]
+ References
No definition available.
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| - Definition
The entire disclosure for comprehensive income, which includes, but is not limited to, 1) the amount of income tax expense or benefit allocated to each component of other comprehensive income, including reclassification adjustments, 2) the reclassification adjustments for each classification of other comprehensive income and 3) the ending accumulated balances for each component of comprehensive income.
+ References
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