Debt and Credit Facilities (Changes in Long-Term Debt) (Detail) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Variable Rate [Domain] \| PSEG [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 700	$ 500
Debt Instrument, Interest Rate, Stated Percentage	0.80%
Medium Term Notes Three Point Zero Percent Due In Two Thousand Twenty Seven [Member] \| PSE And G [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 425
Debt Instrument, Interest Rate, Stated Percentage	3.00%

Face (par) amount of debt instrument at time of issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant