Inventories (Tables)

3 Months Ended

Mar. 31, 2018

Inventory Disclosure [Abstract]

Schedule of Inventories

Inventories at March 31, 2018 and December 31, 2017 were as follows (in millions):

	March 31, 2018			December 31, 2017
Raw materials and supplies	$	175.7		$	162.8
Work-in-process	931.8			955.5
Finished goods	181.2			165.0
Total inventories at current cost	1,288.7			1,283.3
Adjustment from current cost to LIFO cost basis	23.1			43.1
Inventory valuation reserves	(101.0		)	(121.5		)
Progress payments	—			(28.8		)
Total inventories, net	$	1,210.8		$	1,176.1

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,
	2018			2017
LIFO benefit (charge)	$	(8.2	)	$	(8.1	)
NRV benefit (charge)	8.2			8.1
Net cost of sales impact	$	—		$	—