Inventories (Tables)

12 Months Ended

Dec. 31, 2014

Inventory Disclosure [Abstract]

Inventories

Inventories (principally using the LIFO method) are comprised of the following:

	December 31,
(Millions of dollars)	2014		2013		2012
Raw materials	$	2,986	$	2,966	$	3,573
Work-in-process	2,455		2,589		2,920
Finished goods	6,504		6,785		8,767
Supplies	260		285		287
Total inventories	$	12,205	$	12,625	$	15,547