Regulatory Matters: CPUC Rehearing Matter and Procurement Audits (Details) - GOLDEN STATE WATER COMPANY - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Regulatory matters:
Capital expenditure approved	$ 1,867	$ (2,450)
Various refunds to customers
Regulatory matters:
Capital expenditure approved	$ (7,319)	$ (8,478)

The net amount of all regulatory assets less all regulatory liabilities as of the end of the period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382

Name:	us-gaap_NetRegulatoryAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant