Face (par) amount of debt instrument at time of issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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No definition available.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Publisher FASB
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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

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- Definition

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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Paragraph 1
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- Definition

The effective interest rate during the reporting period.

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- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
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Short-term and Long-term Borrowings (Details) - USD ($)	1 Months Ended	3 Months Ended
Short-term and Long-term Borrowings (Details) - USD ($)	Mar. 31, 2016	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Debt Instrument [Line Items]
Proceeds from long-term debt, net of expenses		$ 0	$ 50,039,000
Cal Water
Debt Instrument [Line Items]
Proceeds from long-term debt, net of expenses			49,823,000
Parent Company
Debt Instrument [Line Items]
Proceeds from long-term debt, net of expenses			$ 0
Revolving Credit Facility
Debt Instrument [Line Items]
Average borrowing rate		1.60%	1.27%
Revolving Credit Facility \| Cal Water
Debt Instrument [Line Items]
Repayment of debt	$ 48,600,000
Outstanding borrowings		$ 75,000,000.0		$ 40,000,000.0
Revolving Credit Facility \| Parent Company
Debt Instrument [Line Items]
Outstanding borrowings		$ 55,100,000		$ 57,100,000
Secured Debt \| Cal Water
Debt Instrument [Line Items]
Debt issuance cost	300,000		$ 300,000
Proceeds from long-term debt, net of expenses	49,700,000
Secured Debt \| First Mortgage Bonds Issue 2 \| Cal Water
Debt Instrument [Line Items]
Debt issued	50,000,000.0		50,000,000.0
Secured Debt \| Series SSS Bond \| Cal Water
Debt Instrument [Line Items]
Debt issued	$ 40,000,000.0		$ 40,000,000.0
Interest rate	4.41%		4.41%
Secured Debt \| Series TTT Bond \| Cal Water
Debt Instrument [Line Items]
Debt issued	$ 10,000,000.0		$ 10,000,000.0
Interest rate	4.61%		4.61%