DERIVATIVE FINANCIAL INSTRUMENTS - DERIVATIVE NOTIONALS (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Interest rate and foreign exchange instruments [Member]
Derivative [Line Items]
Notional amount of derivative	$ 306	$ 306
Foreign Exchange [Member]
Derivative [Line Items]
Notional amount of derivative	1,242	1,158
Cash Flow Hedging [Member] \| Interest Rate Contract [Member]
Derivative [Line Items]
Notional amount of derivative	1,259	594
San Diego Gas and Electric Company [Member] \| Cash Flow Hedging [Member] \| Interest Rate Contract [Member]
Derivative [Line Items]
Notional amount of derivative	$ 0	$ 142

Nominal or face amount used to calculate payments on the derivative liability.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

Name:	us-gaap_DerivativeLiabilityNotionalAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant