v3.19.3.a.u2
Pension And Other Postretirement Benefits (Fair Value Of Benefit Plan Assets) (Details) - USD ($)
$ in Millions
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
U.S. [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets $ 13,636 $ 11,134 $ 12,782
U.S. [Member] | Total At Fair Value [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, net asset value [1] 4,226 3,246  
Fair value of plan assets 13,628 11,126  
U.S. [Member] | U.S. Equity Securities [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, net asset value [1] 1,960 1,397  
Fair value of plan assets 1,960 1,397  
U.S. [Member] | Non-U.S. Equity Securities [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, net asset value [1] 1,656 1,218  
Fair value of plan assets 1,656 1,218  
U.S. [Member] | Private Equity [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, net asset value [1] 499 516  
Fair value of plan assets 499 516  
U.S. [Member] | Corporate Debt Securities [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, net asset value [1] 1 1  
Fair value of plan assets 4,933 4,796  
U.S. [Member] | Government Debt Securities [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, net asset value [1] 2 2  
Fair value of plan assets 4,472 3,087  
U.S. [Member] | Asset-Backed Debt Securities [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, net asset value [1] 1 1  
Fair value of plan assets 1 1  
U.S. [Member] | Cash [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, net asset value [1] 107 111  
Fair value of plan assets 107 111  
U.S. [Member] | Insurance Contracts At Contract Value [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 8 8  
U.S. [Member] | Fair Value Inputs Level 2 [Member] | Total At Fair Value [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, fair value hierarchy 9,402 7,880  
U.S. [Member] | Fair Value Inputs Level 2 [Member] | Corporate Debt Securities [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, fair value hierarchy [2] 4,932 4,795  
U.S. [Member] | Fair Value Inputs Level 2 [Member] | Government Debt Securities [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, fair value hierarchy [2] 4,470 3,085  
Pension Benefits - Non-U.S. [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 22,916 19,486 $ 21,461
Pension Benefits - Non-U.S. [Member] | Total At Fair Value [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, net asset value [1] 22,210 18,908  
Fair value of plan assets 22,894 19,465  
Pension Benefits - Non-U.S. [Member] | U.S. Equity Securities [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, net asset value [1] 3,436 2,648  
Fair value of plan assets 3,436 2,648  
Pension Benefits - Non-U.S. [Member] | Non-U.S. Equity Securities [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, net asset value [1] 3,015 2,436  
Fair value of plan assets 3,085 2,493  
Pension Benefits - Non-U.S. [Member] | Private Equity [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, net asset value [1] 489 513  
Fair value of plan assets 489 513  
Pension Benefits - Non-U.S. [Member] | Corporate Debt Securities [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, net asset value [1] 4,486 3,713  
Fair value of plan assets 4,615 3,815  
Pension Benefits - Non-U.S. [Member] | Government Debt Securities [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, net asset value [1] 10,511 9,326  
Fair value of plan assets 10,930 9,666  
Pension Benefits - Non-U.S. [Member] | Asset-Backed Debt Securities [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, net asset value [1] 212 218  
Fair value of plan assets 233 246  
Pension Benefits - Non-U.S. [Member] | Cash [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, net asset value [1] 61 54  
Fair value of plan assets 106 84  
Pension Benefits - Non-U.S. [Member] | Insurance Contracts At Contract Value [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 22 21  
Pension Benefits - Non-U.S. [Member] | Fair Value Inputs Level 1 [Member] | Total At Fair Value [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, fair value hierarchy 383 327  
Pension Benefits - Non-U.S. [Member] | Fair Value Inputs Level 1 [Member] | Non-U.S. Equity Securities [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, fair value hierarchy [3] 70 57  
Pension Benefits - Non-U.S. [Member] | Fair Value Inputs Level 1 [Member] | Government Debt Securities [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, fair value hierarchy [4] 280 243  
Pension Benefits - Non-U.S. [Member] | Fair Value Inputs Level 1 [Member] | Cash [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, fair value hierarchy 33 27  
Pension Benefits - Non-U.S. [Member] | Fair Value Inputs Level 2 [Member] | Total At Fair Value [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, fair value hierarchy 301 230  
Pension Benefits - Non-U.S. [Member] | Fair Value Inputs Level 2 [Member] | Corporate Debt Securities [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, fair value hierarchy [2] 129 102  
Pension Benefits - Non-U.S. [Member] | Fair Value Inputs Level 2 [Member] | Government Debt Securities [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, fair value hierarchy [2] 139 97  
Pension Benefits - Non-U.S. [Member] | Fair Value Inputs Level 2 [Member] | Asset-Backed Debt Securities [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, fair value hierarchy [2] 21 28  
Pension Benefits - Non-U.S. [Member] | Fair Value Inputs Level 2 [Member] | Cash [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets, fair value hierarchy [5] $ 12 $ 3  
[1] Per ASU 2015-07, certain instruments that are measured at fair value using the Net Asset Value (NAV) per share practical expedient have not been categorized in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the total value of plan assets.
[2] For corporate, government and asset-backed debt securities, fair value is based on observable inputs of comparable market transactions.
[3] For non-U.S. equity securities held in separate accounts, fair value is based on observable quoted prices on active exchanges.
[4] For government debt securities that are traded on active exchanges, fair value is based on observable quoted prices.
[5] For cash balances that are subject to withdrawal penalties or other adjustments, the fair value is treated as a Level 2 input.