Inventories (Tables)

3 Months Ended

Mar. 31, 2018

Inventory Disclosure [Abstract]

Inventories

($ in millions)	March 31, 2018		December 31, 2017
Finished products		$1,235		$1,083
Work in process	200		177
Raw materials	493		437
Supplies	35		33
Total Inventories		$1,963		$1,730