Inventories (Tables)

3 Months Ended

Mar. 31, 2019

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, 2019		December 31, 2018
Raw materials	$	100.1	$	90.4
Work in process	39.0		42.2
Finished goods	87.0		81.9
	$	226.1	$	214.5