Inventories (Tables)

6 Months Ended

Jun. 30, 2018

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)	June 30, 2018		December 31, 2017
Raw materials	$	90.2	$	88.6
Work in process	39.0		31.8
Finished goods	79.0		94.8
	$	208.2	$	215.2