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v3.19.3

Joint Ventures (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended | 19 Months Ended |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Mar. 31, 2018 | Sep. 30, 2019 | Sep. 30, 2018 | Oct. 01, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Cash and cash equivalents | $ 511.3 | $ 153.5 |  | $ 511.3 | $ 153.5 |  | $ 382.0 | $ 141.6
Sales to noncontrolling interests |  |  |  | 0.0 | 14.4 |  |  |
Gain on joint venture deconsolidation | 0.0 | 0.0 |  | 0.0 | 15.9 |  |  |
Income (loss) from equity method investments | (2.4) | 0.2 |  | (8.7) | 2.5 |  |  |
Investment in subsidiaries | $ 0.0 |  |  | $ 0.0 |  |  | $ 0.0 |
Next Gen Alloys LLC |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Joint venture ownership percentage | 51.00% |  |  | 51.00% |  |  |  |
Cash and cash equivalents | $ 6.1 |  |  | $ 6.1 |  |  |  |
Sales to noncontrolling interests |  |  | $ 2.7 |  |  |  |  |
Allegheny & Tsingshan Stainless |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Sales to noncontrolling interests |  |  |  |  | 12.0 |  |  |
Equity method investment ownership percentage | 50.00% |  |  | 50.00% |  |  |  |
Uniti |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Equity method investment ownership percentage | 50.00% |  |  | 50.00% |  |  |  |
Tsingshan Group | Allegheny & Tsingshan Stainless |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Joint venture ownership percentage by unaffiliated entity | 50.00% |  |  | 50.00% |  |  |  |
VSMPO | Uniti |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Joint venture ownership percentage by unaffiliated entity | 50.00% |  |  | 50.00% |  |  |  |
Flat Rolled Products | Shanghai STAL Precision Stainless Steel Co Ltd |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Joint venture ownership percentage | 60.00% |  |  | 60.00% |  |  |  |
Cash and cash equivalents | $ 47.4 |  |  | $ 47.4 |  |  |  |
Flat Rolled Products | Allegheny & Tsingshan Stainless |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Income (loss) from equity method investments | (2.6) | (0.3) |  | (9.9) | 0.2 |  |  |
Investment in subsidiaries | 1.2 |  |  | 1.2 |  |  |  |
Due from Affiliates | 36.7 |  |  | 36.7 |  |  |  |
Flat Rolled Products | Uniti |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Income (loss) from equity method investments | $ 0.2 | $ 0.5 |  | $ 1.2 | $ 2.3 |  |  |
Flat Rolled Products | China Baowu Steel Group Corporation Limited | Shanghai STAL Precision Stainless Steel Co Ltd |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Joint venture ownership percentage by unaffiliated entity | 40.00% |  |  | 40.00% |  |  |  |
Forecast | Allegheny & Tsingshan Stainless |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |
Sales to noncontrolling interests |  |  |  |  |  | $ 17.5 |  |

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