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Employee Benefits (Schedule Of Net Benefit Costs, Other Changes in Plan Assets and Benefit Obligation Recognized In Other Comprehensive Income) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items] |  |  |
Settlement benefits | $ (14) |  | $ (25)
Expected net loss, Next Fiscal Year | 0 |  |
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year | 3 |  |
Other Postretirement Benefits Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year | 0 |  |
United States [Member] | Pension Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Service cost | 3 | $ 3 | 3
Administrative expenses | 3 | 4 | 3
Interest Cost | 17 | 23 | 24
Expected return on plan assets | (35) | (33) | (42)
Net amortization | 0 | 0 | (1)
Settlement benefits | 0 | 0 | 14
Net periodic benefit cost (gain) | (12) | (3) | (27)
Net loss (gain) emerging | 22 | 20 | 20
Settlement gain | 0 | 0 | (14)
Other Comprehensive Income (Loss), Defined Benefit Plan, Effect on plan change, before tax | 0 | 0 | 0
Amortization of net gain (loss) | 0 | 0 | 1
Total recognized in OCI | 22 | 20 | 35
Total net periodic benefit cost and OCI | 10 | 17 | 8
United States [Member] | Other Postretirement Benefits Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Service cost | 1 | 1 | 1
Interest Cost | 1 | 2 | 2
Net amortization | 0 | 0 | 0
Net periodic benefit cost (gain) | 2 | 3 | 3
Net loss (gain) emerging | 3 | 3 | (1)
Total recognized in OCI | 3 | 3 | (1)
Total net periodic benefit cost and OCI | 5 | 6 | 2
Foreign Plan [Member] | Pension Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Service cost | 2 | 2 | 2
Administrative expenses | 0 | 0 | 0
Interest Cost | 2 | 3 | 3
Expected return on plan assets | (1) | (1) | (1)
Net amortization | 1 | 0 | 1
Settlement benefits | 0 | 0 | 0
Net periodic benefit cost (gain) | 4 | 4 | 5
Net loss (gain) emerging | 13 | 13 | 1
Settlement gain | 0 | 0 | 0
Other Comprehensive Income (Loss), Defined Benefit Plan, Effect on plan change, before tax | 0 | (4) | 0
Amortization of net gain (loss) | (1) | 0 | (1)
Total recognized in OCI | 12 | 9 | 0
Total net periodic benefit cost and OCI | 16 | 13 | 5
Foreign Plan [Member] | Other Postretirement Benefits Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Service cost | 0 | 0 | 0
Interest Cost | 0 | 0 | 0
Net amortization | 0 | 0 | 0
Net periodic benefit cost (gain) | 0 | 0 | 0
Net loss (gain) emerging | 0 | 0 | (1)
Total recognized in OCI | 0 | 0 | (1)
Total net periodic benefit cost and OCI | $ 0 | $ 0 | $ (1)

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