XML 72 R46.htm IDEA: XBRL DOCUMENT v3.19.2
Commodity Inventories - Summary of the Major Classes of Commodity Inventories (Detail) - USD ($)
$ in Millions
Jun. 30, 2019
Dec. 31, 2018
Energy Related Inventory [Abstract]    
Oil $ 159 $ 139
Natural gas 7 18
NGLs 58 78
Total commodity inventories $ 224 $ 235