Debt [Line Items]

No definition available.

Name:	pcg_DebtLineItems
Namespace Prefix:	pcg_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

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

+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of borrowings classified as other, maturing within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(a)(7))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

The cash outflow from settlement of a long-term debt security issued by a state, certain agencies or authorities, a local government, or development corporation to finance the construction of air- or water-pollution control facilities or sewage or solid waste disposal facilities pursuant to federal law. The bonds are backed by the credit of the beneficiary of the financing rather than the credit of the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

Name:	us-gaap_RepaymentsOfPollutionControlBond
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16(a))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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

- Definition

For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, the maximum amount borrowed at any time during the period.

+ References

No definition available.

+ Details

Name:	us-gaap_ShorttermDebtMaximumAmountOutstandingDuringPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	dei_LegalEntityAxis=pcg_UtilityMember
Namespace Prefix:
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Period Type:

- Details

Name:	us-gaap_RegulatoryAssetAxis=pcg_PollutionControlBondsSeriesNineteenNinetySixCEFAndNineteenNinetySevenBMember
Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_RegulatoryAssetAxis=pcg_PollutionControlBondsSeriesTwoThousandAndNineToDMember
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- Details

Name:	us-gaap_RegulatoryAssetAxis=pcg_PollutionControlBondsSeriesTwoThousandandFourMember
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- Details

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- Details

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- Details

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- Details

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- Details

Name:	us-gaap_RegulatoryAssetAxis=pcg_SeniorNotesThreePointThreeZeroPercentDueTwoThousandTwentySevenMember
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- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
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- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
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- Details

Name:	us-gaap_RangeAxis=pcg_FloatingRateSeniorNotesMember
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Debt (Narrative) (Details) - Utility [Member] - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2017	Jun. 30, 2017
Debt [Line Items]
Short term borrowing outstanding	$ 250
Pollution Control Bonds Series 1996 C, E, F, And 1997 B [Member]
Debt [Line Items]
Debt instrument, face amount	614
Pollution Control Bonds Series 2009 A-B [Member]
Debt [Line Items]
Debt instrument, face amount	149
Pollution Control Bonds Series 2004 A-D [Member]
Debt [Line Items]
Repayments Of Pollution Control Bond	345
Pollution Control Bonds Series 2008 F, G, and 2010 E [Member]
Debt [Line Items]
Debt instrument, face amount	$ 145
Pollution Control Bonds Series 2008 G [Member]
Debt [Line Items]
Debt instrument, interest rate	1.05%
Pollution Control Bonds Series Two Thousand Eight F And Two Thousand Ten E [Member]
Debt [Line Items]
Debt instrument, interest rate	1.75%
Senior Notes, 4.00%, Due 2046 [Member]
Debt [Line Items]
Debt instrument, interest rate	4.00%
Senior Notes	$ 200
Senior Notes, 3.30%, Due 2027 [Member]
Debt [Line Items]
Debt instrument, interest rate	3.30%
Senior Notes	$ 400
Minimum [Member] \| Pollution Control Bonds Series 1996 C, E, F, And 1997 B [Member]
Debt [Line Items]
Debt instrument, interest rate	0.88%
Minimum [Member] \| Pollution Control Bonds Series 2009 A-B [Member]
Debt [Line Items]
Debt instrument, interest rate	0.89%
Maximum [Member] \| Pollution Control Bonds Series 1996 C, E, F, And 1997 B [Member]
Debt [Line Items]
Debt instrument, interest rate	0.95%
Maximum [Member] \| Pollution Control Bonds Series 2009 A-B [Member]
Debt [Line Items]
Debt instrument, interest rate	0.89%
Floating Rate Senior Notes [Member]
Debt [Line Items]
Floating rate unsecured term loan, matured 2017		$ 250