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Commitments and Contingencies (Environmental) (Details) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019
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Site Contingency [Line Items] |  |
Accruals for environmental remediation, dismantling, and decontamination | $ 10 | $ 11
Former TEL Plant Site Louisiana and Houston, Texas Plant Site [Member] |  |
Site Contingency [Line Items] |  |
Accruals for environmental remediation, dismantling, and decontamination | 8 | 8
Accrual for environmental remediation, dismantling, and decontamination, undiscounted | 9 | 10
Former TEL Plant Site Louisiana [Member] |  |
Site Contingency [Line Items] |  |
Accrual for remediation of groundwater and soil | 4 | 4
Houston, Texas Plant Site [Member] |  |
Site Contingency [Line Items] |  |
Accrual for remediation of groundwater and soil | $ 4 | $ 3
Minimum [Member] | Former TEL Plant Site Louisiana and Houston, Texas Plant Site [Member] |  |
Site Contingency [Line Items] |  |
Discount rate | 3.00% | 3.00%
Maximum [Member] | Former TEL Plant Site Louisiana and Houston, Texas Plant Site [Member] |  |
Site Contingency [Line Items] |  |
Discount rate | 9.00% | 9.00%

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- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859 + Details
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