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v3.20.2

Inventories (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2019
Inventory [Line Items] |  |  |  |  |
Raw materials and supplies | $ 210.5 |  | $ 210.5 |  | $ 164.9
Work-in-process | 717.9 |  | 717.9 |  | 899.6
Finished goods | 191.1 |  | 191.1 |  | 161.3
Total inventories at current cost | 1,119.5 |  | 1,119.5 |  | 1,225.8
Adjustment from current cost to LIFO cost basis | 41.1 |  | 41.1 |  | 33.6
Inventory valuation reserves | (124.7) |  | (124.7) |  | (104.1)
Total inventories, net | 1,035.9 |  | 1,035.9 |  | 1,155.3
LIFO benefit (charge) |  |  | 7.5 | $ (1.4) |
NRV benefit (charge) |  |  | (7.5) | 1.3 |
Net cost of sales impact | 0.0 | $ 0.0 | 0.0 | $ (0.1) |
Net Realizable Value Reserve [Member] |  |  |  |  |
Inventory [Line Items] |  |  |  |  |
Inventory valuation reserves | $ (41.1) |  | $ (41.1) |  | $ (33.6)

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