DERIVATIVES - FAIR VALUE (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Oil Collars and Calls | Other current assets
Gross and net fair values of outstanding derivatives (in millions)
Netting, asset		$ 0
Total fair value, asset		25
Oil Collars and Calls | Other current assets | Level 1
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative asset, gross		0
Oil Collars and Calls | Other current assets | Level 2
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative asset, gross		25
Oil Collars and Calls | Other current assets | Level 3
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative asset, gross		0
Oil Collars and Calls | Deferred credits and other liabilities - other
Gross and net fair values of outstanding derivatives (in millions)
Netting, liability		0
Total fair value, liability		(42)
Oil Collars and Calls | Deferred credits and other liabilities - other | Level 1
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative liability, gross		0
Oil Collars and Calls | Deferred credits and other liabilities - other | Level 2
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative liability, gross		(42)
Oil Collars and Calls | Deferred credits and other liabilities - other | Level 3
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative liability, gross		0
Marketing Derivatives
Gross and net fair values of outstanding derivatives (in millions)
Collateral deposited with clearinghouses and brokers	$ 110	85
Marketing Derivatives | Other current assets
Gross and net fair values of outstanding derivatives (in millions)
Netting, asset	(1,645)	(1,204)
Total fair value, asset	44	31
Marketing Derivatives | Other current assets | Level 1
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative asset, gross	1,516	1,155
Marketing Derivatives | Other current assets | Level 2
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative asset, gross	173	80
Marketing Derivatives | Other current assets | Level 3
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative asset, gross	0	0
Marketing Derivatives | Long-term receivables and other assets, net
Gross and net fair values of outstanding derivatives (in millions)
Netting, asset	(4)	(7)
Total fair value, asset	1	2
Marketing Derivatives | Long-term receivables and other assets, net | Level 1
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative asset, gross	4	7
Marketing Derivatives | Long-term receivables and other assets, net | Level 2
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative asset, gross	1	2
Marketing Derivatives | Long-term receivables and other assets, net | Level 3
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative asset, gross	0	0
Marketing Derivatives | Accrued liabilities
Gross and net fair values of outstanding derivatives (in millions)
Netting, liability	1,645	1,204
Total fair value, liability	(159)	(129)
Marketing Derivatives | Accrued liabilities | Level 1
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative liability, gross	(1,608)	(1,252)
Marketing Derivatives | Accrued liabilities | Level 2
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative liability, gross	(196)	(81)
Marketing Derivatives | Accrued liabilities | Level 3
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative liability, gross	0	0
Marketing Derivatives | Deferred credits and other liabilities - other
Gross and net fair values of outstanding derivatives (in millions)
Netting, liability	4	7
Total fair value, liability	0	0
Marketing Derivatives | Deferred credits and other liabilities - other | Level 1
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative liability, gross	(4)	(7)
Marketing Derivatives | Deferred credits and other liabilities - other | Level 2
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative liability, gross	0	0
Marketing Derivatives | Deferred credits and other liabilities - other | Level 3
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative liability, gross	0	0
Interest Rate Swaps
Gross and net fair values of outstanding derivatives (in millions)
Collateral paid netted against derivative liabilities	323	374
Interest Rate Swaps | Accrued liabilities
Gross and net fair values of outstanding derivatives (in millions)
Netting, liability	0	0
Total fair value, liability	(315)	(936)
Interest Rate Swaps | Accrued liabilities | Level 1
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative liability, gross	0	0
Interest Rate Swaps | Accrued liabilities | Level 2
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative liability, gross	(315)	(936)
Interest Rate Swaps | Accrued liabilities | Level 3
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative liability, gross	0	0
Interest Rate Swaps | Deferred credits and other liabilities - other
Gross and net fair values of outstanding derivatives (in millions)
Netting, liability	0	0
Total fair value, liability	(436)	(822)
Interest Rate Swaps | Deferred credits and other liabilities - other | Level 1
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative liability, gross	0	0
Interest Rate Swaps | Deferred credits and other liabilities - other | Level 2
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative liability, gross	(436)	(822)
Interest Rate Swaps | Deferred credits and other liabilities - other | Level 3
Gross and net fair values of outstanding derivatives (in millions)
Commodity contract derivative liability, gross	$ 0	$ 0