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Gross carrying amount before accumulated amortization as of the balance sheet date of intangible assets related to Real Estate Investments having a reasonably expected period of economic benefit.

+ References

No definition available.

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- Definition

Real Estate Selling Expenses

+ References

No definition available.

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- Definition

The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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- Definition

Aggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements.

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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 210.7-03.1(d))

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- Definition

Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Subparagraph (e)

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

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

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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (a)

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-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 3)

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Cash received from the sale of real estate that is held for investment, that is, it is part of an investing activity during the period.

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (c)

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- Definition

The amount of property, by major property class, net of accumulated depreciation, subject to or available for lease as of the balance sheet date.

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)

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Useful life on which depreciation was computed for entities with a substantial portion of business acquiring and holding investment real estate, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Subparagraph (SX 210.12-28)

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-Subparagraph (SX 210.5-04.(c) Schedule III)

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-Publisher SEC

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-Number 210

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-Article 12

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-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph c

-Subparagraph Schedule III

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Amount of real estate investment property which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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Summary of Significant Accounting Policies (Real Estate Investments) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Aug. 01, 2014	Jun. 30, 2014	Feb. 01, 2013	Aug. 02, 2012
Components of Real Estate Investments [Abstract]
Land	$ 17,297us-gaap_Land	$ 18,892us-gaap_Land
Buildings and improvements	56,168	59,256
Intangibles	329sjw_RealEstateInvestmentsIntangibles	329sjw_RealEstateInvestmentsIntangibles
Total real estate investment	73,794	78,477
Gain on sale of real estate investment	554us-gaap_GainLossOnSaleOfProperties	1,063us-gaap_GainLossOnSaleOfProperties	910us-gaap_GainLossOnSaleOfProperties
Operating Leases, Future Minimum Payments Receivable [Abstract]
2013	5,345
2014	5,514
2015	5,612
2016	4,789
2017	3,753
Thereafter	13,691
California Non-Utility Property [Member]
Components of Real Estate Investments [Abstract]
Proceeds from sale of real estate held-for-investment				300
Gain on sale of real estate investment				281
Selling expense				10
Texas Retail Buildings [Member]
Components of Real Estate Investments [Abstract]
Proceeds from sale of real estate held-for-investment					4,450
Gain on sale of real estate investment					273
Selling expense					169
Connecticut Warehouse [Member]
Components of Real Estate Investments [Abstract]
Proceeds from sale of real estate held-for-investment						9,200
Gain on sale of real estate investment						1,063
Selling expense						369
Florida Warehouse [Member]
Components of Real Estate Investments [Abstract]
Proceeds from sale of real estate held-for-investment							5,821
Gain on sale of real estate investment							910
Selling expense							304
Minimum [Member]
Components of Real Estate Investments [Abstract]
Estimated useful life	5 years
Maximum [Member]
Components of Real Estate Investments [Abstract]
Estimated useful life	39 years
Land and Building [Member]
Assets Leased or Available for Lease [Abstract]
Assets leased or available for lease	$ 72,402	$ 77,082