The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Publisher FASB
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Period Type:	instant

- 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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-Publisher FASB
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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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Lines of Credit - Schedule of Lines of Credit (Details) - Revolving Credit Facility - Line of Credit - USD ($)	Dec. 31, 2023	Feb. 06, 2023	Dec. 31, 2022	Oct. 31, 2022
Line of Credit Facility [Line Items]
Line Limit	$ 350,000,000
Amounts Outstanding	171,500,000		$ 159,578,000
Unused Portion	178,500,000
Syndicated Credit Agreement
Line of Credit Facility [Line Items]
Line Limit	300,000,000
Amounts Outstanding	121,500,000		115,000,000
Unused Portion	178,500,000
SJW Group Credit Agreement Maturing August 2028
Line of Credit Facility [Line Items]
Line Limit	50,000,000
Amounts Outstanding	10,000,000		0
Unused Portion	40,000,000
SJWC Credit Agreement Maturing August 2028
Line of Credit Facility [Line Items]
Line Limit	140,000,000
Amounts Outstanding	56,000,000		95,000,000
Unused Portion	84,000,000
CTWS Credit Agreement Maturing August 2028
Line of Credit Facility [Line Items]
Line Limit	90,000,000
Amounts Outstanding	53,000,000		20,000,000
Unused Portion	37,000,000
SJWTX Credit Agreement Maturing August 2028
Line of Credit Facility [Line Items]
Line Limit	20,000,000
Amounts Outstanding	2,500,000		0
Unused Portion	17,500,000
CTWS Credit Agreement Maturing August 2028
Line of Credit Facility [Line Items]
Line Limit	10,000,000			$ 10,000
Amounts Outstanding	10,000,000		4,578,000
Unused Portion	0
CTWS Credit Agreement Maturing May 2025
Line of Credit Facility [Line Items]
Line Limit	40,000,000	$ 40,000,000
Amounts Outstanding	40,000,000		$ 40,000,000
Unused Portion	$ 0