Employee Benefit Plans (Pension and Post Retirement Asset Allocations in Accordance with Investment Guidelines) (Details) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 |
Defined Benefit Plan Disclosure [Line Items] | | | |
Notional | $ 445,049 | $ 379,860 | |
Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Net Value of investment of securities lending collateral invested in short-term bond | 586 | 135 | |
Liability for securities lending collateral | 586 | 135 | |
Defined Benefit Plan, Plan Assets, Amount | 14,897 | 13,906 | $ 12,807 |
Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 1,589 | 1,557 | 1,432 |
Investment Measure at Net Asset Value as a practical expedient | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 279 | 273 | |
Equities | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 23 | 22 | |
Equities | Level 1 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Equities | Level 2 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 23 | 22 | |
Equities | Level 3 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Fixed Maturities | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 7,213 | 6,712 | |
Fixed Maturities | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 67 | 141 | |
Fixed Maturities | Level 1 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 129 | 44 | |
Fixed Maturities | Level 1 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 19 | 4 | |
Fixed Maturities | Level 2 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 7,049 | 6,624 | |
Fixed Maturities | Level 2 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 48 | 136 | |
Fixed Maturities | Level 3 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 35 | 44 | |
Fixed Maturities | Level 3 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 1 | |
Other | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 2,561 | 2,285 | |
Other | Level 1 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Other | Level 2 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Other | Level 3 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 2,561 | 2,285 | |
Net assets in the fair value hierarchy | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 10,612 | 9,685 | |
Net assets in the fair value hierarchy | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 255 | 326 | |
Net assets in the fair value hierarchy | Level 1 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 129 | 44 | |
Net assets in the fair value hierarchy | Level 1 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 184 | 167 | |
Net assets in the fair value hierarchy | Level 2 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 7,049 | 6,624 | |
Net assets in the fair value hierarchy | Level 2 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 71 | 158 | |
Net assets in the fair value hierarchy | Level 3 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 3,434 | 3,017 | |
Net assets in the fair value hierarchy | Level 3 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 1 | |
Variable Life Insurance Policies at contract value | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 1,055 | 958 | |
Mortgage-backed | Fixed Maturities | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 1 | 1 | |
Mortgage-backed | Fixed Maturities | Level 1 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Mortgage-backed | Fixed Maturities | Level 2 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 1 | 1 | |
Mortgage-backed | Fixed Maturities | Level 3 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
U.S. Equities | Equities | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 14 | 14 | |
U.S. Equities | Equities | Level 1 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
U.S. Equities | Equities | Level 2 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 14 | 14 | |
U.S. Equities | Equities | Level 3 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
International Equities | Equities | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 9 | 8 | |
International Equities | Equities | Level 1 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
International Equities | Equities | Level 2 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 9 | 8 | |
International Equities | Equities | Level 3 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Other U.S. government securities | Fixed Maturities | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 985 | 783 | |
Other U.S. government securities | Fixed Maturities | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 9 | 20 | |
Other U.S. government securities | Fixed Maturities | Level 1 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Other U.S. government securities | Fixed Maturities | Level 1 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Other U.S. government securities | Fixed Maturities | Level 2 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 985 | 783 | |
Other U.S. government securities | Fixed Maturities | Level 2 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 9 | 20 | |
Other U.S. government securities | Fixed Maturities | Level 3 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Other U.S. government securities | Fixed Maturities | Level 3 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
U.S. government securities (state & other) | Fixed Maturities | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 588 | 562 | |
U.S. government securities (state & other) | Fixed Maturities | Level 1 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
U.S. government securities (state & other) | Fixed Maturities | Level 2 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 588 | 562 | |
U.S. government securities (state & other) | Fixed Maturities | Level 3 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Non-U.S. government securities | Fixed Maturities | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 103 | 93 | |
Non-U.S. government securities | Fixed Maturities | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 1 | 2 | |
Non-U.S. government securities | Fixed Maturities | Level 1 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Non-U.S. government securities | Fixed Maturities | Level 1 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Non-U.S. government securities | Fixed Maturities | Level 2 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 103 | 93 | |
Non-U.S. government securities | Fixed Maturities | Level 2 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 1 | 2 | |
Non-U.S. government securities | Fixed Maturities | Level 3 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Non-U.S. government securities | Fixed Maturities | Level 3 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Corporate bonds | Fixed Maturities | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 4,290 | 4,281 | |
Corporate bonds | Fixed Maturities | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 7 | 53 | |
Corporate bonds | Fixed Maturities | Level 1 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Corporate bonds | Fixed Maturities | Level 1 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Corporate bonds | Fixed Maturities | Level 2 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 4,290 | 4,281 | |
Corporate bonds | Fixed Maturities | Level 2 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 7 | 53 | |
Corporate bonds | Fixed Maturities | Level 3 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Corporate bonds | Fixed Maturities | Level 3 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Asset-backed | Fixed Maturities | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 25 | 22 | |
Asset-backed | Fixed Maturities | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 2 | 16 | |
Asset-backed | Fixed Maturities | Level 1 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Asset-backed | Fixed Maturities | Level 1 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Asset-backed | Fixed Maturities | Level 2 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 25 | 22 | |
Asset-backed | Fixed Maturities | Level 2 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 2 | 16 | |
Asset-backed | Fixed Maturities | Level 3 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Asset-backed | Fixed Maturities | Level 3 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Collateralized Mortgage Obligations | Fixed Maturities | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 614 | 485 | |
Collateralized Mortgage Obligations | Fixed Maturities | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 3 | 10 | |
Collateralized Mortgage Obligations | Fixed Maturities | Level 1 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Collateralized Mortgage Obligations | Fixed Maturities | Level 1 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Collateralized Mortgage Obligations | Fixed Maturities | Level 2 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 614 | 485 | |
Collateralized Mortgage Obligations | Fixed Maturities | Level 2 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 3 | 10 | |
Collateralized Mortgage Obligations | Fixed Maturities | Level 3 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Collateralized Mortgage Obligations | Fixed Maturities | Level 3 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Collateralized Loan Obligations | Fixed Maturities | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 441 | 397 | |
Collateralized Loan Obligations | Fixed Maturities | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 4 | 15 | |
Collateralized Loan Obligations | Fixed Maturities | Level 1 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Collateralized Loan Obligations | Fixed Maturities | Level 1 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Collateralized Loan Obligations | Fixed Maturities | Level 2 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 441 | 397 | |
Collateralized Loan Obligations | Fixed Maturities | Level 2 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 4 | 15 | |
Collateralized Loan Obligations | Fixed Maturities | Level 3 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Collateralized Loan Obligations | Fixed Maturities | Level 3 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Interest Rate Swaps | Fixed Maturities | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Notional | 13 | 2,462 | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 2 | |
Interest Rate Swaps | Fixed Maturities | Level 1 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Interest Rate Swaps | Fixed Maturities | Level 2 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 2 | |
Interest Rate Swaps | Fixed Maturities | Level 3 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Registered investment companies | Fixed Maturities | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 96 | 7 | |
Registered investment companies | Fixed Maturities | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 19 | 4 | |
Registered investment companies | Fixed Maturities | Level 1 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 96 | 7 | |
Registered investment companies | Fixed Maturities | Level 1 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 19 | 4 | |
Registered investment companies | Fixed Maturities | Level 2 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Registered investment companies | Fixed Maturities | Level 2 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Registered investment companies | Fixed Maturities | Level 3 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Registered investment companies | Fixed Maturities | Level 3 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Registered investment companies | Short-term Investments | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 165 | 163 | |
Registered investment companies | Short-term Investments | Level 1 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 165 | 163 | |
Registered investment companies | Short-term Investments | Level 2 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Registered investment companies | Short-term Investments | Level 3 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Other | Fixed Maturities | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 70 | 79 | |
Other | Fixed Maturities | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 1 | |
Other | Fixed Maturities | Level 1 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 33 | 37 | |
Other | Fixed Maturities | Level 1 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Other | Fixed Maturities | Level 2 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 2 | (2) | |
Other | Fixed Maturities | Level 2 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Other | Fixed Maturities | Level 3 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 35 | 44 | |
Other | Fixed Maturities | Level 3 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 1 | |
Equities | Fixed Maturities | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 22 | 20 | |
Equities | Fixed Maturities | Level 1 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Equities | Fixed Maturities | Level 2 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 22 | 20 | |
Equities | Fixed Maturities | Level 3 | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Unrealized gain (loss) on investment of securities lending collateral | Fixed Maturities | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Unrealized gain (loss) on investment of securities lending collateral | Fixed Maturities | Level 1 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Unrealized gain (loss) on investment of securities lending collateral | Fixed Maturities | Level 2 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Unrealized gain (loss) on investment of securities lending collateral | Fixed Maturities | Level 3 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Partnerships | Real Estate | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 838 | 688 | |
Partnerships | Real Estate | Level 1 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Partnerships | Real Estate | Level 2 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Partnerships | Real Estate | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 838 | 688 | 482 |
Partnerships | Real Estate | Level 3 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 838 | 688 | |
Partnerships | Other | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 1,234 | 973 | |
Partnerships | Other | Level 1 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Partnerships | Other | Level 2 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Partnerships | Other | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 1,234 | 973 | 830 |
Partnerships | Other | Level 3 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 1,234 | 973 | |
Hedge Fund | Other | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 1,327 | 1,312 | |
Hedge Fund | Other | Level 1 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Hedge Fund | Other | Level 2 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 | |
Hedge Fund | Other | Level 3 | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 1,327 | 1,312 | $ 1,463 |
Hedge Fund | Other | Level 3 | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 1,327 | 1,312 | |
Pooled separate accounts | Investment Measure at Net Asset Value as a practical expedient | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 2,659 | 2,869 | |
Common/collective trusts | Investment Measure at Net Asset Value as a practical expedient | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 1,440 | 1,185 | |
United Kingdom insurance pooled funds | Investment Measure at Net Asset Value as a practical expedient | Pension Benefits | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | 186 | 167 | |
Net assets at fair value | Postretirement | | | |
Defined Benefit Plan Disclosure [Line Items] | | | |
Defined Benefit Plan, Plan Assets, Amount | $ 534 | $ 599 | |