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Inventories (Tables)

12 Months Ended

Dec. 31, 2020

Inventory Disclosure [Abstract]

Schedule of Inventory

Inventories at December 31, 2020 and 2019 were as follows (in millions):

						2020						2019
Raw materials and supplies						$	207.6					$	164.9
Work-in-process						690.7						899.6
Finished goods						181.6						161.3
Total inventories at current cost						1,079.9						1,225.8
Adjustment from current cost to LIFO cost basis						44.1						33.6
Inventory valuation reserves						(126.9)						(104.1)
Total inventories, net						$	997.1					$	1,155.3

Schedule of Inventory Valuation Impact on Income

						Fiscal year ended December 31,
						2020			2019			2018
LIFO benefit (charge)						$	10.5		$	25.5		$	(28.6)
NRV benefit (charge)						(10.5)			(25.6)			27.9
Net cost of sales impact						$	—		$	(0.1)		$	(0.7)

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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

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Schedule of Inventory Valuation Impact on Income [Table Text Block]

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