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Inventories (Tables) | 6 Months Ended
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Jun. 30, 2019
Inventory Disclosure [Abstract] |
Schedule of Inventories | Inventories at June 30, 2019 and December 31, 2018 were as follows (in millions):
| June 30, 2019 |  | December 31, 2018
Raw materials and supplies | $ | 194.1 |  |  | $ | 191.5 |
Work-in-process | 917.8 |  |  | 914.1 |
Finished goods | 182.7 |  |  | 191.1 |
Total inventories at current cost | 1,294.6 |  |  | 1,296.7 |
Adjustment from current cost to LIFO cost basis | 13.9 |  |  | 2.9 |
Inventory valuation reserves | (91.0 | ) |  | (88.5 | )
Total inventories, net | $ | 1,217.5 |  |  | $ | 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):
|  | Six months ended June 30,
|  | 2019 |  | 2018
LIFO benefit (charge) |  | $ | 5.8 |  |  | $ | (27.5 | )
NRV benefit (charge) |  | (5.9 | ) |  | 27.5 |
Net cost of sales impact |  | $ | (0.1 | ) |  | $ | — |

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