Commitments (Details) $ in Thousands	12 Months Ended
Dec. 31, 2023 USD ($) unit
GSWC \| Low income rate assistance balancing accounts
Estimated future minimum payments
Total	$ 9,000
GSWC \| Water Supply
Estimated future minimum payments
2024	491
2025	441
2026	391
2027	391
2028	213
Thereafter	805
Total	2,732
GSWC \| Water Supply \| Various third parties
Purchase commitments
Remaining amount of commitment	1,300
GSWC \| Water Supply \| Other various third parties
Estimated future minimum payments
Total	$ 1,400
BVES
Estimated future minimum payments
Number of renewable energy credits that would be purchased \| unit	578,000
BVES \| Renewables Portfolio Standard [Member]
Estimated future minimum payments
Derivative, Term of Contract	10 years
BVES \| Renewables Portfolio Standard (Bundled Product)
Estimated future minimum payments
Derivative, Term of Contract	11 years
BVES \| Electric Power Purchase Commitments
Estimated future minimum payments
Total	$ 45,800
Minimum \| BVES
Purchase commitments
Derivative, Term of Contract	3 years
Maximum \| BVES
Purchase commitments
Derivative, Term of Contract	5 years
Purchase power contract \| Minimum \| BVES
Purchase commitments
Derivative, Term of Contract	3 years
Purchase power contract \| Maximum \| BVES
Purchase commitments
Derivative, Term of Contract	5 years

Represents the period of agreement with a third party to purchase renewable energy credits.

No definition available.

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- Definition

Represents the number of renewable energy credits that would be purchased over a contractual period of time.

+ References

No definition available.

+ Details

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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Minimum amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(17))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(25))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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- Definition

Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

+ References

No definition available.

+ Details

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- Definition

Amount of purchase arrangement to be paid after fifth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

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- Definition

Amount of purchase arrangement to be paid in fifth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

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- Definition

Amount of purchase arrangement to be paid in fourth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

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- Definition

Amount of purchase arrangement to be paid in next fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

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- Definition

Amount of purchase arrangement to be paid in second fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

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- Definition

Amount of purchase arrangement to be paid in third fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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