Inventories (Tables)

12 Months Ended

Dec. 31, 2016

Inventory Disclosure [Abstract]

Schedule of inventory classes

The classes of inventory as of December 31 are summarized as follows ($ in millions):

	2016		2015
Finished goods	$	198.3	$	184.1
Work in process		79.3		77.1
Raw materials		267.0		261.7
Total	$	544.6	$	522.9