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Inventories (Tables) | 9 Months Ended
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Sep. 30, 2021
Inventory Disclosure [Abstract] |
Schedule of Inventories | Inventories at September 30, 2021 and December 31, 2020 were as follows (in millions):
| September 30, 2021 |  | December 31, 2020
Raw materials and supplies | $ | 195.5 |  |  | $ | 207.6 |
Work-in-process | 804.0 |  |  | 690.7 |
Finished goods | 125.1 |  |  | 181.6 |
Total inventories at current cost | 1,124.6 |  |  | 1,079.9 |
Adjustment from current cost to LIFO cost basis | 0.3 |  |  | 44.1 |
Inventory valuation reserves | (69.1) |  |  | (126.9) |
Total inventories, net | $ | 1,055.8 |  |  | $ | 997.1 |
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,
|  | 2021 |  | 2020
LIFO benefit (charge) |  | $ | (43.8) |  |  | $ | 7.5 |
NRV benefit (charge) |  | 43.8 |  |  | (7.5) |
Net cost of sales impact |  | $ | — |  |  | $ | — |

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