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Employee Benefits (Narrative Defined Benefit Plan) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Remeasurement due to Settlement |  |  | $ 26
Defined Benefit Plan, Target Allocation Percentage of Assets, Long-Term | 60.00% |  |
Defined Benefit Plan, Target Allocation Percentage of Assets, Short-Term | 40.00% |  |
Minimum [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Target Allocation Percentage of Assets, Discretionary Range | 10.00% |  |
Minimum [Member] | United States [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Funded Status, Percentage | 80.00% |  |
Equity Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 60.00% |  |
Fixed Income [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 40.00% |  |
Pension Plan [Member] | United States [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Other Comprehensive Income (Loss), Defined Benefit Plan, Settlement and Curtailment Gain (Loss), before Tax | $ 0 | $ 0 | 14
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year | 1 |  |
Pension Plan [Member] | Foreign Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Other Comprehensive Income (Loss), Defined Benefit Plan, Settlement and Curtailment Gain (Loss), before Tax | 0 | 0 | 0
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Other Comprehensive Income (Loss), Defined Benefit Plan, Settlement and Curtailment Gain (Loss), before Tax | $ 0 | $ 0 | $ 14

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- Definition Amount of (increase) decrease to benefit obligation of defined benefit plan from remeasurement due to settlement. Excludes decrease to benefit obligation for settlement payment. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(10) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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