Inventories (Tables)

12 Months Ended

Dec. 31, 2017

Inventory Disclosure [Abstract]

Inventories

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

	December 31,
(Millions of dollars)	2017		2016
Raw materials	$	2,802	$	2,102
Work-in-process	2,254		1,719
Finished goods	4,761		4,576
Supplies	201		217
Total inventories	$	10,018	$	8,614