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Fair Value Measurements (Details) - USD ($) $ in Millions | Mar. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | $ 33,921 | $ 32,284
Trading fixed maturities |  | 249 | 254
Assets of managed investment entities (“MIE”) |  | 3,906 | 4,047
Variable annuity assets (separate accounts) | [1] | 595 | 608
Total assets accounted for at fair value |  | 40,606 | 39,155
Liabilities: |  |  |
Liabilities of managed investment entities |  | 3,656 | 3,781
Total liabilities accounted for at fair value |  | 5,108 | 5,156
Annuity benefits accumulated [Member] |  |  |
Liabilities: |  |  |
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities |  | 1,450 | 1,369
Derivatives in long-term debt [Member] |  |  |
Liabilities: |  |  |
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities |  | (8) | (2)
Other liabilities — derivatives [Member] |  |  |
Liabilities: |  |  |
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities |  | 10 | 8
U.S. Government and government agencies [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 338 | 307
States, municipalities and political subdivisions [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 7,052 | 6,856
Foreign government [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 147 | 154
Residential Mortgage Backed Securities [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 3,772 | 3,529
Commercial Mortgage Backed Securities [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 2,136 | 2,187
Asset-backed Securities [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 5,130 | 4,934
All other corporate [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 15,346 | 14,317
Fixed maturities [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 33,921 | 32,284
Trading fixed maturities |  | 249 | 254
Equity securities [Member] |  |  |
Assets: |  |  |
Equity securities — AFS and trading |  | 1,648 | 1,719
Other assets — derivatives [Member] |  |  |
Assets: |  |  |
Derivatives included in other investments and other assets |  | 13 | 2
Level 1 [Member] |  |  |
Assets: |  |  |
Assets of managed investment entities (“MIE”) |  | 177 | 309
Variable annuity assets (separate accounts) | [1] | 0 | 0
Total assets accounted for at fair value |  | 1,688 | 1,834
Liabilities: |  |  |
Liabilities of managed investment entities |  | 165 | 289
Total liabilities accounted for at fair value |  | 165 | 289
Level 1 [Member] | Annuity benefits accumulated [Member] |  |  |
Liabilities: |  |  |
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities |  | 0 | 0
Level 1 [Member] | Derivatives in long-term debt [Member] |  |  |
Liabilities: |  |  |
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities |  | 0 | 0
Level 1 [Member] | Other liabilities — derivatives [Member] |  |  |
Liabilities: |  |  |
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities |  | 0 | 0
Level 1 [Member] | U.S. Government and government agencies [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 105 | 100
Level 1 [Member] | States, municipalities and political subdivisions [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 0 | 0
Level 1 [Member] | Foreign government [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 0 | 0
Level 1 [Member] | Residential Mortgage Backed Securities [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 0 | 0
Level 1 [Member] | Commercial Mortgage Backed Securities [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 0 | 0
Level 1 [Member] | Asset-backed Securities [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 0 | 0
Level 1 [Member] | All other corporate [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 37 | 50
Level 1 [Member] | Fixed maturities [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 142 | 150
Trading fixed maturities |  | 10 | 13
Level 1 [Member] | Equity securities [Member] |  |  |
Assets: |  |  |
Equity securities — AFS and trading |  | 1,359 | 1,362
Level 1 [Member] | Other assets — derivatives [Member] |  |  |
Assets: |  |  |
Derivatives included in other investments and other assets |  | 0 | 0
Level 2 [Member] |  |  |
Assets: |  |  |
Assets of managed investment entities (“MIE”) |  | 3,705 | 3,712
Variable annuity assets (separate accounts) | [1] | 595 | 608
Total assets accounted for at fair value |  | 37,147 | 35,685
Liabilities: |  |  |
Liabilities of managed investment entities |  | 3,468 | 3,468
Total liabilities accounted for at fair value |  | 3,470 | 3,474
Level 2 [Member] | Annuity benefits accumulated [Member] |  |  |
Liabilities: |  |  |
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities |  | 0 | 0
Level 2 [Member] | Derivatives in long-term debt [Member] |  |  |
Liabilities: |  |  |
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities |  | (8) | (2)
Level 2 [Member] | Other liabilities — derivatives [Member] |  |  |
Liabilities: |  |  |
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities |  | 10 | 8
Level 2 [Member] | U.S. Government and government agencies [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 218 | 192
Level 2 [Member] | States, municipalities and political subdivisions [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 6,960 | 6,767
Level 2 [Member] | Foreign government [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 147 | 154
Level 2 [Member] | Residential Mortgage Backed Securities [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 3,559 | 3,305
Level 2 [Member] | Commercial Mortgage Backed Securities [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 2,098 | 2,148
Level 2 [Member] | Asset-backed Securities [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 4,629 | 4,464
Level 2 [Member] | All other corporate [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 14,579 | 13,634
Level 2 [Member] | Fixed maturities [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 32,190 | 30,664
Trading fixed maturities |  | 239 | 241
Level 2 [Member] | Equity securities [Member] |  |  |
Assets: |  |  |
Equity securities — AFS and trading |  | 131 | 217
Level 2 [Member] | Other assets — derivatives [Member] |  |  |
Assets: |  |  |
Derivatives included in other investments and other assets |  | 13 | 2
Level 3 [Member] |  |  |
Assets: |  |  |
Assets of managed investment entities (“MIE”) |  | 24 | 26
Variable annuity assets (separate accounts) | [1] | 0 | 0
Total assets accounted for at fair value |  | 1,771 | 1,636
Liabilities: |  |  |
Liabilities of managed investment entities |  | 23 | 24
Total liabilities accounted for at fair value |  | 1,473 | 1,393
Level 3 [Member] | Annuity benefits accumulated [Member] |  |  |
Liabilities: |  |  |
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities |  | 1,450 | 1,369
Level 3 [Member] | Derivatives in long-term debt [Member] |  |  |
Liabilities: |  |  |
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities |  | 0 | 0
Level 3 [Member] | Other liabilities — derivatives [Member] |  |  |
Liabilities: |  |  |
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities |  | 0 | 0
Level 3 [Member] | U.S. Government and government agencies [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 15 | 15
Level 3 [Member] | States, municipalities and political subdivisions [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 92 | 89
Level 3 [Member] | Foreign government [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 0 | 0
Level 3 [Member] | Residential Mortgage Backed Securities [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 213 | 224
Level 3 [Member] | Commercial Mortgage Backed Securities [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 38 | 39
Level 3 [Member] | Asset-backed Securities [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 501 | 470
Level 3 [Member] | All other corporate [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 730 | 633
Level 3 [Member] | Fixed maturities [Member] |  |  |
Assets: |  |  |
Available for sale (AFS) fixed maturities |  | 1,589 | 1,470
Trading fixed maturities |  | 0 | 0
Level 3 [Member] | Equity securities [Member] |  |  |
Assets: |  |  |
Equity securities — AFS and trading |  | 158 | 140
Level 3 [Member] | Other assets — derivatives [Member] |  |  |
Assets: |  |  |
Derivatives included in other investments and other assets |  | 0 | 0
Equity index call options [Member] | Other investments — derivatives [Member] |  |  |
Assets: |  |  |
Derivatives included in other investments and other assets |  | 274 | 241
Equity index call options [Member] | Level 1 [Member] | Other investments — derivatives [Member] |  |  |
Assets: |  |  |
Derivatives included in other investments and other assets |  | 0 | 0
Equity index call options [Member] | Level 2 [Member] | Other investments — derivatives [Member] |  |  |
Assets: |  |  |
Derivatives included in other investments and other assets |  | 274 | 241
Equity index call options [Member] | Level 3 [Member] | Other investments — derivatives [Member] |  |  |
Assets: |  |  |
Derivatives included in other investments and other assets |  | $ 0 | $ 0
[1] | Variable annuity liabilities equal the fair value of variable annuity assets.

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