The Merger - Preliminary Purchase Price Allocation (Details) - Anadarko $ in Millions	Aug. 08, 2019 USD ($)
Fair value of assets acquired:
Current assets	$ 3,590
Anadarko's Africa Assets held for sale	10,746
Investments in unconsolidated entities	2,430
Property, plant and equipment, net	48,771
Other assets	797
Intangible assets - WES Midstream	2,400
Amount attributable to assets acquired	78,209
Fair value of liabilities assumed:
Current liabilities	3,677
Liabilities of Anadarko's Africa Assets held for sale	2,329
Long-term debt	12,829
Deferred income taxes	10,040
Asset retirement obligations	2,728
Pension and post retirement obligations	1,125
Non-current derivative liabilities	1,279
Other long-term liabilities	2,308
Amount attributable to liabilities assumed	43,722
Net assets	34,487
Less: Fair value of noncontrolling interests in WES Midstream	4,875
Fair value of net assets acquired	29,612
Goodwill - WES Midstream	6,074
Total Merger consideration	35,686
WES Midstream
Fair value of assets acquired:
Property, plant and equipment, net	9,475
Fair value of liabilities assumed:
Long-term debt	$ 7,407

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