Regulatory Matters (Details 3) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Regulatory matters:
Other Liabilities, Current	$ 18,760,000us-gaap_OtherLiabilitiesCurrent	$ 12,962,000us-gaap_OtherLiabilitiesCurrent
GSWC
Regulatory matters:
Under (over) collection	125,704,000	122,681,000
Other Liabilities, Current	18,659,000	12,880,000
Other Regulatory Assets Net [Member]
Regulatory matters:
Other Liabilities, Current	5,500,000
Other Regulatory Assets Net [Member] \| GSWC
Regulatory matters:
Under (over) collection	17,487,000	25,086,000
Low income rate assistance balancing accounts \| GSWC
Regulatory matters:
Increase in Revenue Requirement, Recoverable through Surcharges	700,000	1,200,000
Under (over) collection	9,109,000	9,979,000
Pension Costs and Other Postretirement Benefit Costs [Member] \| GSWC
Regulatory matters:
Regulatory Assets	40,700,000
Under (over) collection	43,426,000	20,241,000
Two-way pension balancing account \| Pension Costs and Other Postretirement Benefit Costs [Member] \| GSWC
Regulatory matters:
Regulatory Assets	2,700,000
Two-way pension balancing account \| Purchase, production, distribution and sale of water \| Pension Costs and Other Postretirement Benefit Costs [Member] \| GSWC
Regulatory matters:
Regulatory Assets	2,800,000
Two-way pension balancing account \| Electric \| Pension Costs and Other Postretirement Benefit Costs [Member] \| GSWC
Regulatory matters:
Regulatory Assets	$ (124,000)

Represents the amount of increase in revenue requirement for difference between the allocated general office costs authorized by the CPUC November 2010 Decision and what was then in rates for allocated general office costs.

No definition available.

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- Definition

The net amount of all regulatory assets less all regulatory liabilities as of the end of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 980

-SubTopic 340

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382

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- Definition

Aggregate carrying amount of current liabilities (due within one year or within the normal operating cycle if longer) not separately disclosed in the balance sheet. Includes costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered and of liabilities not separately disclosed.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6911-107765

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6904-107765

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- Definition

The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

+ References

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