EQUITY (Changes in Equity) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 19,472
Comprehensive income	445
Common stock issued	35
Share-based compensation	34
Preferred stock dividend requirement	0
Preferred stock dividend requirement of subsidiary	(3)	$ (3)
Ending balance	19,983
Pacific Gas & Electric Co
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	19,747
Comprehensive income	452	570
Common stock issued	0
Share-based compensation	0
Preferred stock dividend requirement	(3)	$ (3)
Preferred stock dividend requirement of subsidiary	0
Ending balance	$ 20,196

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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The aggregate value of preferred stock dividends and other adjustments necessary to derive net income apportioned to common stockholders.

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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