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Inventories (Tables) | 12 Months Ended
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Dec. 31, 2017
Inventory Disclosure [Abstract] |
Schedule of Inventory | Inventories at December 31, 2017 and 2016 were as follows (in millions):
|  | 2017 |  | 2016
Raw materials and supplies |  | $ | 162.8 |  |  | $ | 149.6 |
Work-in-process |  | 955.5 |  |  | 837.9 |
Finished goods |  | 165.0 |  |  | 161.7 |
Total inventories at current cost |  | 1,283.3 |  |  | 1,149.2 |
Adjustment from current cost to LIFO cost basis |  | 43.1 |  |  | 97.3 |
Inventory valuation reserves |  | (121.5 | ) |  | (169.0 | )
Progress payments |  | (28.8 | ) |  | (40.5 | )
Total inventories, net |  | $ | 1,176.1 |  |  | $ | 1,037.0 |
Schedule of Inventory Valuation Impact on Income |
|  | Fiscal year ended December 31,
|  | 2017 | 2016 | 2015
LIFO benefit (charge) |  | $ | (54.2 | ) | $ | (39.1 | ) | $ | 131.6 |
NRV benefit (charge) |  | 54.0 |  | 39.9 |  | (131.5 | )
Net cost of sales impact |  | $ | (0.2 | ) | $ | 0.8 |  | $ | 0.1 |

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- Definition Disclosure of the values of the inventory by category at the balance sheet date including raw materials, work-in-process, finished goods at current cost, adjusted for LIFO reserves and progress payments + References No definition available. + Details
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