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Inventories (Tables) | 3 Months Ended
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Mar. 31, 2020
Inventory Disclosure [Abstract] |
Schedule of Inventories | Inventories at March 31, 2020 and December 31, 2019 were as follows (in millions):
| March 31, 2020 |  | December 31, 2019
Raw materials and supplies | $ | 174.8 |  |  | $ | 164.9 |
Work-in-process | 908.9 |  |  | 899.6 |
Finished goods | 171.7 |  |  | 161.3 |
Total inventories at current cost | 1,255.4 |  |  | 1,225.8 |
Adjustment from current cost to LIFO cost basis | 45.6 |  |  | 33.6 |
Inventory valuation reserves | (119.9 | ) |  | (104.1 | )
Total inventories, net | $ | 1,181.1 |  |  | $ | 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):
|  | Three months ended March 31,
|  | 2020 |  | 2019
LIFO benefit |  | $ | 12.0 |  |  | $ | 1.8 |
NRV charge |  | (12.0 | ) |  | (1.9 | )
Net cost of sales impact |  | $ | — |  |  | $ | (0.1 | )

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