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Inventories Narrative (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Inventory [Line Items] |  |  |
LIFO inventory amount | $ 776.1 | $ 794.3 |
Inventory valuation reserves | (104.1) | (88.5) |
Effect of LIFO liquidation on income | (1.8) | 0.8 | $ (4.6)
Inventories, net | 1,155.3 | 1,211.1 |
Inventory valuation charges due to market-based valuation |  |  | $ 17.7
Adjustment from current cost to LIFO cost basis | 33.6 | 2.9 |
ASU 2014-09 | Transferred over Time |  |  |
Inventory [Line Items] |  |  |
Inventories, net |  | 5.4 |
Net Realizable Value Reserve |  |  |
Inventory [Line Items] |  |  |
Inventory valuation reserves | (33.6) | $ (8.0) |
Forged Products |  |  |
Inventory [Line Items] |  |  |
Adjustment from current cost to LIFO cost basis | $ 5.2 |  |

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