Fair Value of Financial Instruments (Fair Value of Assets and Liabilities on a Recurring Basis) (Details) - USD ($) $ in Millions | Sep. 30, 2018 | Dec. 31, 2017 |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | $ 246,814 | $ 245,265 |
Liabilities measured at fair value | | (2,382) | (3,689) |
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 1,449 | 1,692 |
Significant Observable Inputs (Level 2) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 239,553 | 238,376 |
Liabilities measured at fair value | | (437) | (1,631) |
Significant Unobservable Inputs (Level 3) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 5,812 | 5,197 |
Liabilities measured at fair value | | (1,945) | (2,058) |
Corporate Bonds [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 80,080 | 82,216 |
Corporate Bonds [Member] | Significant Observable Inputs (Level 2) [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 76,871 | 79,125 |
Corporate Bonds [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 3,209 | 3,091 |
ABS [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 985 | 974 |
ABS [Member] | Significant Observable Inputs (Level 2) [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 954 | 947 |
ABS [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 31 | 27 |
U.S. Government Bonds [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 409 | 567 |
U.S. Government Bonds [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 391 | 556 |
U.S. Government Bonds [Member] | Significant Observable Inputs (Level 2) [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 18 | 6 |
U.S. Government Bonds [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | | 5 |
Foreign Government Bonds [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 459 | 451 |
Foreign Government Bonds [Member] | Significant Observable Inputs (Level 2) [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 351 | 341 |
Foreign Government Bonds [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 108 | 110 |
RMBS [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 3,287 | 3,465 |
RMBS [Member] | Significant Observable Inputs (Level 2) [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 3,280 | 3,453 |
RMBS [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 7 | 12 |
CMBS [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 748 | 600 |
CMBS [Member] | Significant Observable Inputs (Level 2) [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 725 | 594 |
CMBS [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 23 | 6 |
CLOs [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 1,362 | 808 |
CLOs [Member] | Significant Observable Inputs (Level 2) [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 1,311 | 717 |
CLOs [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 51 | 91 |
State And Municipal Bonds [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 5,218 | 5,119 |
State And Municipal Bonds [Member] | Significant Observable Inputs (Level 2) [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 5,218 | 5,119 |
Hybrid And Redeemable Preferred Securities [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 613 | 640 |
Hybrid And Redeemable Preferred Securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 74 | 71 |
Hybrid And Redeemable Preferred Securities [Member] | Significant Observable Inputs (Level 2) [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 462 | 493 |
Hybrid And Redeemable Preferred Securities [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fixed Maturity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 77 | 76 |
Equity AFS Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | | 246 |
Equity AFS Securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | | 28 |
Equity AFS Securities [Member] | Significant Observable Inputs (Level 2) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | | 56 |
Equity AFS Securities [Member] | Significant Unobservable Inputs (Level 3) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | | 162 |
Trading Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 1,440 | 1,620 |
Trading Securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 43 | 73 |
Trading Securities [Member] | Significant Observable Inputs (Level 2) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 1,379 | 1,498 |
Trading Securities [Member] | Significant Unobservable Inputs (Level 3) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 18 | 49 |
Equity Securities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 112 | |
Equity Securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 28 | |
Equity Securities [Member] | Significant Observable Inputs (Level 2) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 58 | |
Equity Securities [Member] | Significant Unobservable Inputs (Level 3) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 26 | |
Derivative Investments [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | [1] | 1,107 | 1,597 |
Derivative Investments [Member] | Significant Observable Inputs (Level 2) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | [1] | 572 | 994 |
Derivative Investments [Member] | Significant Unobservable Inputs (Level 3) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | [1] | 535 | 603 |
Other investments [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 149 | 150 |
Other investments [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 149 | 150 |
Cash And Invested cash [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 1,460 | 1,628 |
Cash And Invested cash [Member] | Significant Observable Inputs (Level 2) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 1,460 | 1,628 |
GLB Direct Embedded Derivatives [Member] | Other Assets [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 1,648 | 903 |
GLB Direct Embedded Derivatives [Member] | Significant Unobservable Inputs (Level 3) [Member] | Other Assets [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 1,648 | 903 |
GLB Ceded Embedded Derivatives [Member] | Other Assets [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 35 | 51 |
GLB Ceded Embedded Derivatives [Member] | Other Liabilities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Liabilities measured at fair value | | (193) | (67) |
GLB Ceded Embedded Derivatives [Member] | Significant Unobservable Inputs (Level 3) [Member] | Other Assets [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 35 | 51 |
GLB Ceded Embedded Derivatives [Member] | Significant Unobservable Inputs (Level 3) [Member] | Other Liabilities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Liabilities measured at fair value | | (193) | (67) |
Separate Account Assets [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 147,658 | 144,219 |
Separate Account Assets [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 764 | 814 |
Separate Account Assets [Member] | Significant Observable Inputs (Level 2) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 146,894 | 143,405 |
Indexed Annuity And Embedded Derivatives [Member] | Other Assets [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 44 | 11 |
Indexed Annuity And Embedded Derivatives [Member] | Future Contract Benefits [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Liabilities measured at fair value | | (1,571) | (1,418) |
Indexed Annuity And Embedded Derivatives [Member] | Significant Unobservable Inputs (Level 3) [Member] | Other Assets [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Assets measured at fair value | | 44 | 11 |
Indexed Annuity And Embedded Derivatives [Member] | Significant Unobservable Inputs (Level 3) [Member] | Future Contract Benefits [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Liabilities measured at fair value | | (1,571) | (1,418) |
Long-term Debt [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Liabilities measured at fair value | | | (1,127) |
Long-term Debt [Member] | Significant Observable Inputs (Level 2) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Liabilities measured at fair value | | | (1,127) |
Reinsurance Related Embedded Derivatives [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Liabilities measured at fair value | | (20) | (57) |
Reinsurance Related Embedded Derivatives [Member] | Significant Observable Inputs (Level 2) [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Liabilities measured at fair value | | (20) | (57) |
Derivative Financial Instruments, Liabilities [Member] | Other Liabilities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Liabilities measured at fair value | [1] | (598) | (1,020) |
Derivative Financial Instruments, Liabilities [Member] | Significant Observable Inputs (Level 2) [Member] | Other Liabilities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Liabilities measured at fair value | [1] | (417) | (447) |
Derivative Financial Instruments, Liabilities [Member] | Significant Unobservable Inputs (Level 3) [Member] | Other Liabilities [Member] | | | |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] | | | |
Liabilities measured at fair value | [1] | $ (181) | $ (573) |
| |
[1] | Derivative investment assets and liabilities presented within the fair value hierarchy are presented on a gross basis by derivative type and not on a master netting basis by counterparty. | |