v3.20.4

Pension And Postretirement Benefits (Schedule Of Fair Value Of Pension And Postretirement Assets And Liabilities By Level) (Details) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | --- | ---
Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | $ 54,606 | $ 53,530 | $ 51,681
Pension Benefits | Assets at fair value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 42,793 | 43,195 |
Pension Benefits | Non-interest bearing cash |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 173 | 85 |
Pension Benefits | Interest bearing cash |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 7 | 529 |
Pension Benefits | Foreign currency contracts |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 3 | 5 |
Pension Benefits | Equity securities: Domestic equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 9,795 | 8,072 |
Pension Benefits | Equity securities: International equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 4,844 | 3,946 |
Pension Benefits | Preferred interest |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 5,771 | 8,806 |
Pension Benefits | Fixed income securities: Corporate bonds and other investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 11,095 | 10,473 |
Pension Benefits | Fixed income securities: Government and municipal bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 6,039 | 6,172 |
Pension Benefits | Fixed income securities: Mortgage-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 443 | 524 |
Pension Benefits | Real estate and real assets |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 2,544 | 2,817 |
Pension Benefits | Securities lending collateral |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 2,056 | 1,761 |
Pension Benefits | Receivable for variation margin |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 23 | 5 |
Pension Benefits | Investments sold short and other liabilities at fair value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | (459) | (515) |
Pension Benefits | Private equity funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | $ 5,154 | $ 4,544 |
Defined Benefit Plan, Plan Assets, Fair Value by Hierarchy and NAV [Extensible List] | us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember | us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember |
Pension Benefits | Real estate funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | $ 1,694 | $ 2,062 |
Defined Benefit Plan, Plan Assets, Fair Value by Hierarchy and NAV [Extensible List] | us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember | us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember |
Pension Benefits | Commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | $ 7,706 | $ 5,710 |
Defined Benefit Plan, Plan Assets, Fair Value by Hierarchy and NAV [Extensible List] | us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember | us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember |
Pension Benefits | Other assets (liabilities) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | $ (2,282) | $ (1,466) |
Postretirement Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 3,843 | 4,145 | 4,277
Postretirement Benefits | Assets at fair value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 2,020 | 2,301 |
Postretirement Benefits | Interest bearing cash |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 799 | 549 |
Postretirement Benefits | Equity securities: Domestic equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 363 | 438 |
Postretirement Benefits | Equity securities: International equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 282 | 265 |
Postretirement Benefits | Fixed income securities: Corporate bonds and other investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 315 | 530 |
Postretirement Benefits | Fixed income securities: Government and municipal bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 139 | 189 |
Postretirement Benefits | Fixed income securities: Mortgage-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 94 | 294 |
Postretirement Benefits | Securities lending collateral |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 28 | 36 |
Postretirement Benefits | Securities lending payable and other liabilities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | (30) | (36) |
Postretirement Benefits | Private equity funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | $ 24 | $ 66 |
Defined Benefit Plan, Plan Assets, Fair Value by Hierarchy and NAV [Extensible List] | us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember | us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember |
Postretirement Benefits | Real estate funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | $ 22 | $ 27 |
Defined Benefit Plan, Plan Assets, Fair Value by Hierarchy and NAV [Extensible List] | us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember | us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember |
Postretirement Benefits | Commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | $ 1,843 | $ 1,797 |
Defined Benefit Plan, Plan Assets, Fair Value by Hierarchy and NAV [Extensible List] | us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember | us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember |
Postretirement Benefits | Other assets (liabilities) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | $ (36) | $ (10) |
Level 1, 2, and 3 | Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 42,334 | 42,680 |
Level 1, 2, and 3 | Postretirement Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 1,990 | 2,265 |
Level 1 | Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 14,979 | 12,255 |
Level 1 | Pension Benefits | Assets at fair value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 15,429 | 12,768 |
Level 1 | Pension Benefits | Non-interest bearing cash |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 173 | 85 |
Level 1 | Pension Benefits | Interest bearing cash |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 7 | 529 |
Level 1 | Pension Benefits | Foreign currency contracts |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 1 | Pension Benefits | Equity securities: Domestic equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 9,784 | 8,068 |
Level 1 | Pension Benefits | Equity securities: International equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 4,821 | 3,929 |
Level 1 | Pension Benefits | Preferred interest |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 1 | Pension Benefits | Fixed income securities: Corporate bonds and other investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 1 | Pension Benefits | Fixed income securities: Government and municipal bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 49 |
Level 1 | Pension Benefits | Fixed income securities: Mortgage-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 1 | Pension Benefits | Real estate and real assets |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 1 | Pension Benefits | Securities lending collateral |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 621 | 103 |
Level 1 | Pension Benefits | Receivable for variation margin |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 23 | 5 |
Level 1 | Pension Benefits | Investments sold short and other liabilities at fair value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | (450) | (513) |
Level 1 | Postretirement Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 1,152 | 964 |
Level 1 | Postretirement Benefits | Assets at fair value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 1,153 | 964 |
Level 1 | Postretirement Benefits | Interest bearing cash |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 497 | 248 |
Level 1 | Postretirement Benefits | Equity securities: Domestic equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 363 | 438 |
Level 1 | Postretirement Benefits | Equity securities: International equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 282 | 265 |
Level 1 | Postretirement Benefits | Fixed income securities: Corporate bonds and other investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 5 | 7 |
Level 1 | Postretirement Benefits | Fixed income securities: Government and municipal bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 6 | 6 |
Level 1 | Postretirement Benefits | Fixed income securities: Mortgage-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 1 | Postretirement Benefits | Securities lending collateral |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 1 | Postretirement Benefits | Securities lending payable and other liabilities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | (1) | 0 |
Level 2 | Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 18,965 | 18,786 |
Level 2 | Pension Benefits | Assets at fair value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 18,973 | 18,788 |
Level 2 | Pension Benefits | Non-interest bearing cash |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 2 | Pension Benefits | Interest bearing cash |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 2 | Pension Benefits | Foreign currency contracts |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 3 | 5 |
Level 2 | Pension Benefits | Equity securities: Domestic equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 2 | Pension Benefits | Equity securities: International equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 11 | 11 |
Level 2 | Pension Benefits | Preferred interest |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 2 | Pension Benefits | Fixed income securities: Corporate bonds and other investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 11,043 | 10,469 |
Level 2 | Pension Benefits | Fixed income securities: Government and municipal bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 6,039 | 6,123 |
Level 2 | Pension Benefits | Fixed income securities: Mortgage-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 442 | 522 |
Level 2 | Pension Benefits | Real estate and real assets |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 2 | Pension Benefits | Securities lending collateral |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 1,435 | 1,658 |
Level 2 | Pension Benefits | Receivable for variation margin |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 2 | Pension Benefits | Investments sold short and other liabilities at fair value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | (8) | (2) |
Level 2 | Postretirement Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 834 | 1,269 |
Level 2 | Postretirement Benefits | Assets at fair value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 863 | 1,305 |
Level 2 | Postretirement Benefits | Interest bearing cash |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 302 | 301 |
Level 2 | Postretirement Benefits | Equity securities: Domestic equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 2 | Postretirement Benefits | Equity securities: International equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 2 | Postretirement Benefits | Fixed income securities: Corporate bonds and other investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 307 | 492 |
Level 2 | Postretirement Benefits | Fixed income securities: Government and municipal bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 132 | 182 |
Level 2 | Postretirement Benefits | Fixed income securities: Mortgage-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 94 | 294 |
Level 2 | Postretirement Benefits | Securities lending collateral |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 28 | 36 |
Level 2 | Postretirement Benefits | Securities lending payable and other liabilities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | (29) | (36) |
Level 3 | Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 8,390 | 11,639 | 11,333
Level 3 | Pension Benefits | Assets at fair value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 8,391 | 11,639 |
Level 3 | Pension Benefits | Non-interest bearing cash |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 3 | Pension Benefits | Interest bearing cash |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 3 | Pension Benefits | Foreign currency contracts |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 3 | Pension Benefits | Equity securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 5,793 | 8,816 | 8,750
Level 3 | Pension Benefits | Equity securities: Domestic equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 11 | 4 |
Level 3 | Pension Benefits | Equity securities: International equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 12 | 6 |
Level 3 | Pension Benefits | Preferred interest |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 5,771 | 8,806 |
Level 3 | Pension Benefits | Fixed Income Funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 53 | 6 | 4
Level 3 | Pension Benefits | Fixed income securities: Corporate bonds and other investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 52 | 4 |
Level 3 | Pension Benefits | Fixed income securities: Government and municipal bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 3 | Pension Benefits | Fixed income securities: Mortgage-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 1 | 2 |
Level 3 | Pension Benefits | Real estate and real assets |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 2,544 | 2,817 | 2,579
Level 3 | Pension Benefits | Securities lending collateral |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 3 | Pension Benefits | Receivable for variation margin |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 3 | Pension Benefits | Investments sold short and other liabilities at fair value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | (1) | 0 |
Level 3 | Postretirement Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 4 | 32 | 13
Level 3 | Postretirement Benefits | Assets at fair value |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 4 | 32 |
Level 3 | Postretirement Benefits | Interest bearing cash |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 3 | Postretirement Benefits | Equity securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 | 1
Level 3 | Postretirement Benefits | Equity securities: Domestic equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 3 | Postretirement Benefits | Equity securities: International equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 3 | Postretirement Benefits | Fixed Income Funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 4 | 32 | 12
Level 3 | Postretirement Benefits | Fixed income securities: Corporate bonds and other investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 3 | 31 |
Level 3 | Postretirement Benefits | Fixed income securities: Government and municipal bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 1 | 1 |
Level 3 | Postretirement Benefits | Fixed income securities: Mortgage-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 3 | Postretirement Benefits | Real estate and real assets |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 | $ 0
Level 3 | Postretirement Benefits | Securities lending collateral |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Level 3 | Postretirement Benefits | Securities lending payable and other liabilities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 0 | 0 |
Assets held at net asset value practical expedient | Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | 14,554 | 12,316 |
Assets held at net asset value practical expedient | Postretirement Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total Plan Net Assets | $ 1,889 | $ 1,890 |

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