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Inventories (Tables) | 9 Months Ended
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Sep. 30, 2020
Inventory Disclosure [Abstract] |
Schedule of Inventories | Inventories at September 30, 2020 and December 31, 2019 were as follows (in millions):
| September 30, 2020 |  | December 31, 2019
Raw materials and supplies | $ | 210.5 |  |  | $ | 164.9 |
Work-in-process | 717.9 |  |  | 899.6 |
Finished goods | 191.1 |  |  | 161.3 |
Total inventories at current cost | 1,119.5 |  |  | 1,225.8 |
Adjustment from current cost to LIFO cost basis | 41.1 |  |  | 33.6 |
Inventory valuation reserves | (124.7) |  |  | (104.1) |
Total inventories, net | $ | 1,035.9 |  |  | $ | 1,155.3 |
Schedule of Inventory Valuation Impact on Income | Impacts to cost of sales for changes in the LIFO costing methodology and associated NRV inventory reserves were as follows (in millions):
|  | Nine months ended September 30,
|  | 2020 |  | 2019
LIFO benefit (charge) |  | $ | 7.5 |  |  | $ | (1.4) |
NRV benefit (charge) |  | (7.5) |  |  | 1.3 |
Net cost of sales impact |  | $ | — |  |  | $ | (0.1) |

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