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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
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

No definition available.

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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

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Period Type:	instant

- 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) - Line of Credit - USD ($)	Dec. 31, 2021	Apr. 23, 2021	Dec. 31, 2020
Revolving Credit Facility
Line of Credit Facility [Line Items]
Line Limit	$ 260,000,000
Amounts Outstanding	62,996,000		$ 175,094,000
Unused Portion	197,004,000
Revolving Credit Facility \| SJWC Credit Agreement Maturing December 2023
Line of Credit Facility [Line Items]
Line Limit	140,000,000
Amounts Outstanding	0		80,000,000
Unused Portion	140,000,000
Revolving Credit Facility \| CTWS Credit Agreement Maturing December 2023
Line of Credit Facility [Line Items]
Line Limit	75,000,000
Amounts Outstanding	22,996,000		55,094,000
Unused Portion	52,004,000
Revolving Credit Facility \| CTWS Credit Agreement Maturing May 2025
Line of Credit Facility [Line Items]
Line Limit	40,000,000
Amounts Outstanding	40,000,000		40,000,000
Unused Portion	0
Revolving Credit Facility \| SJWTX, Inc. Credit Agreement Maturing December 2023
Line of Credit Facility [Line Items]
Line Limit	5,000,000
Amounts Outstanding	0		$ 0
Unused Portion	$ 5,000,000
Revolving Credit Facility \| SJWC Credit Agreement \| Chase Bank, N.A. \| SJWC
Line of Credit Facility [Line Items]
Line Limit		$ 140,000,000
Revolving Credit Facility \| SJWTX Credit Agreement \| Chase Bank, N.A. \| SJW Corp. and SJWTX, Inc.
Line of Credit Facility [Line Items]
Line Limit		5,000,000
Standby Letters of Credit \| SJWC Credit Agreement \| Chase Bank, N.A. \| SJWC
Line of Credit Facility [Line Items]
Line Limit		15,000,000
Standby Letters of Credit \| SJWTX Credit Agreement \| Chase Bank, N.A. \| SJW Corp. and SJWTX, Inc.
Line of Credit Facility [Line Items]
Line Limit		$ 1,000,000