Debt Instrument, Covenant, Capitalization Ratio

No definition available.

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- Definition

The effective interest rate at the end of the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ 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

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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- Details

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Balance Type:
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- Details

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Data Type:	na
Balance Type:
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- Details

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Balance Type:
Period Type:

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Lines of Credit - Narrative (Details)		12 Months Ended
Lines of Credit - Narrative (Details)	Apr. 23, 2021 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Feb. 06, 2023 USD ($)	Aug. 02, 2022 USD ($)	Aug. 01, 2022 USD ($)
Line of Credit Facility [Line Items]
Repayments of lines of credit		$ 62,197,000	$ 208,722,000	$ 218,289,000
Revolving Credit Facility \| Line of Credit
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity		$ 350,000,000
Revolving Credit Facility \| Line of Credit \| SJW Group
Line of Credit Facility [Line Items]
Line of credit cost of borrowing rate		3.41%	1.32%
Revolving Credit Facility \| Line of Credit \| Credit Agreement
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity						$ 300,000,000
Capitalization ratio						0.70
Revolving Credit Facility \| Line of Credit \| SJWC Credit Agreement
Line of Credit Facility [Line Items]
Repayments of lines of credit	$ 140,000,000
Revolving Credit Facility \| Line of Credit \| SJWTX Credit Agreement
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 5,000,000
Revolving Credit Facility \| Line of Credit \| CTWS Credit Agreement Maturing May 2025
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity		$ 40,000,000
Revolving Credit Facility \| Line of Credit \| CTWS Credit Agreement Maturing May 2025 \| Subsequent Event
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity					$ 40,000,000
Revolving Credit Facility \| Line of Credit \| CTWS \| Amended and Restated Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity						$ 10,000,000	$ 75,000,000