Subsequent Event	3 Months Ended
Mar. 31, 2021
Subsequent Events [Abstract]
Subsequent Event	Subsequent EventGSWC's 9.56% private placement notes issued in the amount of $28.0 million and due in 2031 can be redeemed, in whole or in part, at the option of GSWC subject to redemption schedules embedded in the agreement. The 9.56% notes are subject to a make-whole premium based on 55 basis points above the applicable Treasury Yield if redeemed prior to May 15, 2021. After May 15, 2021, the maximum redemption premium is 3.0% of par value. On April 23, 2021, GSWC notified the note holders of its intent to redeem the notes on May 24, 2021. Pursuant to the agreement, the prepayment of the notes will include the redemption premium of 3.0% on par value, or $840,000. GSWC recovers redemption premiums in its embedded cost of debt as filed in cost of capital proceedings where the cost savings from redeeming high interest rate debt are passed on to customers.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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