v3.20.2

Subsequent Events​ (Details) $ in Millions | May 13, 2020 USD ($) | Apr. 02, 2020 USD ($) | Oct. 30, 2020 USD ($) | Mar. 01, 2020 USD ($) | Dec. 31, 2019 USD ($) | Feb. 08, 2019 company | Oct. 01, 2018 USD ($) claimants
--- | --- | --- | --- | --- | --- | --- | ---
Subsequent Event [Line Items] |  |  |  |  |  |  |
Number of publicly traded companies | company |  |  |  |  |  | 2 |
Disposed of by sale | Hard Alloy Extrusions Plant in South Korea |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |
Consideration received |  |  |  | $ 55 |  |  |
Disposed of by sale | Texarkana Rolling Mill and Cast House [Member] |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |
Consideration received |  |  |  |  |  |  | $ 302
Disposal Group, Including Discontinued Operation, Book Value |  |  |  |  |  |  | $ 63
Period of Operationalizing Rolling Mill Equipment of Transaction | claimants |  |  |  |  |  |  | 36
Disposed of by sale | Texarkana Rolling Mill and Cast House [Member] | Achievement of Milestones [Member] |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |
Consideration received |  |  |  |  | $ 25 |  | $ 50
Disposed of by sale | Texarkana Rolling Mill and Cast House [Member] | Achievement of Milestones [Member] | Subsequent events |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |
Consideration received |  |  | $ 25 |  |  |  |
Senior Secured Credit Facility | First-Lien Revolving Credit Facility | Revolving Credit Facility |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |
Proceeds from revolving credit facility | $ 500 | $ 500 |  |  |  |  |

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