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Equity Method Investements (Details) lb in Millions, $ in Millions |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 17, 2015 lb | Dec. 31, 2020 USD ($) lb | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Nov. 12, 2019 USD ($) | Oct. 28, 2019
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Investments in joint ventures |  |  | $ 225 |  |  |
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity |  | $ 166 |  |  |  |
Return of investment |  | (44) | 0 | $ 0 |  |
Equity Method Investments |  | 1,059 | 1,112 |  |  |
LACC, LLC [Member] |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Ownership interest (in percent) |  |  |  |  | 34.80% | 12.00%
Increase in Equity Method Investment |  | $ 0 | 817 |  | $ 817 |
Investments in and Advances to Affiliates, Proportionate Share Of Production, Mass | lb |  | 787 |  |  |  |
Investments in and Advances to Affiliates, at Fair Value |  | $ 961 | 1,038 | $ 183 |  |
Cash contributions |  | 4 | 45 |  |  |
Depreciation and amortization |  | (37) | (7) |  |  |
Return of investment |  | (44) | 0 |  |  |
other equity method investments [Member] |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Equity Method Investments |  | 98 | 74 |  |  |
Affiliates [Member] |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Plant capacity (in lbs) | lb | 2,200 |  |  |  |  |
Lotte Chemical Corporation [Member] |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Revenue, Remaining Performance Obligation, Amount |  | 78 |  |  |  |
Contract with Customer, Liability |  | $ 12 | 7 |  |  |
LACC, LLC [Member] |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Related Party Transaction, Reimbursement Agreement, Term |  | 6 years 6 months |  |  |  |
Revenue, Remaining Performance Obligation, Amount |  | $ 57 |  |  |  |
Contract with Customer, Liability |  | $ 10 | $ 5 |  |  |
LACC, LLC [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01 |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period |  | 25 years |  |  |  |

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