NATURE OF BUSINESS, SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND OTHER - Property, Plant and Equipment (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($)
Property, Plant and Equipment, Net [Abstract]
Maximum time period after which costs of exploratory wells are charged to expense if determination of proved reserves has not been made	1 year
Net capitalized costs attributable to unproved properties	$ 232
Maximum \| Gas plant and power plant assets
Property, Plant and Equipment, Net [Abstract]
Expected useful lives	30 years
Maximum \| Other non- producing property and equipment
Property, Plant and Equipment, Net [Abstract]
Expected useful lives	20 years

Capitalized costs of unproven properties that include fee ownership or a lease, concession, or other interest representing the right to extract oil or gas subject to such terms as may be imposed by the conveyance of that interest.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61926-109447

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-URI http://asc.fasb.org/topic&trid=2145477

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61901-109447

Name:	us-gaap_CapitalizedCostsMineralInterestsInUnprovedProperties
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant