Inventories

12 Months Ended

Dec. 31, 2017

Inventory Disclosure [Abstract]

Inventories

4.  Inventories

Inventories at December 31 were as follows:

	2017		2016
	(In millions)
Crude oil and natural gas liquids	$	59	$	77
Materials and supplies		173		246
Total Inventories	$	232	$	323