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Inventories (Tables) | 3 Months Ended
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Mar. 31, 2019
Inventory Disclosure [Abstract] |
Schedule of Inventories | Inventories at March 31, 2019 and December 31, 2018 were as follows (in millions):
| March 31, 2019 |  | December 31, 2018
Raw materials and supplies | $ | 212.5 |  |  | $ | 191.5 |
Work-in-process | 941.3 |  |  | 914.1 |
Finished goods | 192.4 |  |  | 191.1 |
Total inventories at current cost | 1,346.2 |  |  | 1,296.7 |
Adjustment from current cost to LIFO cost basis | 4.7 |  |  | 2.9 |
Inventory valuation reserves | (96.5 | ) |  | (88.5 | )
Total inventories, net | $ | 1,254.4 |  |  | $ | 1,211.1 |
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):
|  | Three months ended March 31,
|  | 2019 |  | 2018
LIFO benefit (charge) |  | $ | 1.8 |  |  | $ | (8.2 | )
NRV benefit (charge) |  | (1.9 | ) |  | 8.2 |
Net cost of sales impact |  | $ | (0.1 | ) |  | $ | — |

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