Inventories (Tables)

3 Months Ended

Mar. 31, 2017

Inventory Disclosure [Abstract]

Inventories

Inventories are valued at the lower of cost (on a first-in, first-out basis) and net realizable value. Inventory balances were as follows:

($ in millions)	March 31, 2017		December 31, 2016
Raw materials	$	81.7	$	78.0
Work in process	33.0		28.9
Finished goods	97.6		92.4
	$	212.3	$	199.3