Assets Leased or Available for Lease [Abstract]

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- Definition

Deferred Gains (Losses) on Sales of Properties

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No definition available.

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- Definition

Number Of Properties Sold

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No definition available.

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- Definition

Properties Selling Expenses

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No definition available.

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- Definition

Real Estate Selling Expenses

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No definition available.

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- Definition

Sales Agreement, Holdback Amount

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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

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- Definition

The net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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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- References

No definition available.

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- Definition

Amount of lease payment to be received by lessor for operating lease in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount of lease payment to be received by lessor for operating lease in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lease payment to be received by lessor for operating lease in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lease payment to be received by lessor for operating lease after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lease payment to be received by lessor for operating lease in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lease payment to be received by lessor for operating lease in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

The cash inflow from the sale of land held for investment; excludes sales of land held as inventory or productive use.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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.

+ References

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- Definition

Amount, after accumulated depreciation, of lessor's underlying asset for which right to use has been conveyed to lessee under operating lease.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References

No definition available.

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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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- Definition

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 and Nonutility Properties (Details) $ in Thousands			12 Months Ended
	Oct. 29, 2021 USD ($) property	Jun. 29, 2021 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2017 USD ($)
Components of Real Estate Investments [Abstract]
Land			$ 12,615	$ 12,615
Buildings and improvements			45,418	45,017
Total real estate investments and nonutility properties			58,033	57,632
Gain on sale of properties		$ 3,000	0	3,000	$ 0
Sales agreement, holdback amount						$ 3,000
Gain on sale of real estate investments			0	927	$ 948
Lessor, Operating Lease, Payments, Fiscal Year Maturity [Abstract]
2023			4,423
2024			3,157
2025			3,034
2026			3,197
2027			3,180
Thereafter			1,679
SJWC
Components of Real Estate Investments [Abstract]
Number of properties sold \| property	2
Proceeds from sale of real estate held-for-investment	$ 13,150
Gain on sale of properties			7,230
Properties selling expenses			277
Deferred gains on sales of properties			$ 5,442
Proceeds from sale of land held-for-investment	2,600
Gain on sale of real estate investments	927
Real estate selling expenses	$ 121
Building and Building Improvements \| Minimum
Components of Real Estate Investments [Abstract]
Estimated useful life			7 years
Building and Building Improvements \| Maximum
Components of Real Estate Investments [Abstract]
Estimated useful life			39 years
Land and Building
Assets Leased or Available for Lease [Abstract]
Assets leased or available for lease			$ 58,730	$ 58,330