SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - NATURE OF OPERATIONS, WES INVESTMENT AND DISCONTINUED OPERATIONS (Details) $ in Millions		5 Months Ended	12 Months Ended
	Aug. 08, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 USD ($) segment	Sep. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
NATURE OF OPERATIONS
Number of reportable segments | segment			3
Summary of significant accounting policies
Equity method investment amounts		$ 6,389	$ 6,389		$ 1,680	$ 1,515
Mozambique LNG Assets | Disposed of by sale
Summary of significant accounting policies
Sale consideration				$ 4,200
WES
Summary of significant accounting policies
Equity method investment amounts		5,128	5,128
Charge recorded as a result of loss of control			1,000
Anadarko Petroleum Corporation
Summary of significant accounting policies
Revenues from date of the Acquisition		4,200
Equity method investment amounts		2,800	$ 2,800
Anadarko Petroleum Corporation | Africa Assets | Assets held for sale
Summary of significant accounting policies
Sale consideration	$ 8,800
WES | Anadarko Petroleum Corporation
Summary of significant accounting policies
Revenues from date of the Acquisition		1,100
Expenses from date of the Acquisition		500
Operating cash flows from date of the Acquisition		498
WES Operating
Summary of significant accounting policies
Non-voting general partner unit interest			2.00%
WES
Summary of significant accounting policies
Limited partner interest			55.40%
Non-voting general partner unit interest			2.00%
Limited partner unit interest			54.50%
Total effective economic interest in WES			56.30%
Pro rata share of net assets		1,900	$ 1,900
Tax basis difference		$ 3,200	$ 3,200
WES
Summary of significant accounting policies
Percentage of unaffiliated unitholders			20.00%
WES | Occidental
Summary of significant accounting policies
Voting percentage for certain unitholder matters, limit			45.00%
Limited partner units percentage			40.00%
Transfer of limited partner interest, percentage			2.00%
Economic interest to general partner, percentage			2.00%
WES | WES Operating
Summary of significant accounting policies
Limited partner interest	98.00%
Public Ownership | WES | WES
Summary of significant accounting policies
Limited partner interest			44.60%