Regulatory Matters - Regulatory Assets, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Regulatory Assets [Line Items]
Total regulatory assets, net in Condensed Consolidated Balance Sheets	$ 139,993	$ 143,343
Less: current regulatory assets, net	8,573	16,068
Total regulatory assets, net, less current portion	131,420	127,275
Income tax temporary differences, net
Regulatory Assets [Line Items]
Total regulatory assets, net in Condensed Consolidated Balance Sheets	62,745	43,434
Postretirement pensions and other postretirement benefits
Regulatory Assets [Line Items]
Total regulatory assets, net in Condensed Consolidated Balance Sheets	30,076	31,493
Business combinations debt premium, net
Regulatory Assets [Line Items]
Total regulatory assets, net in Condensed Consolidated Balance Sheets	15,490	17,396
Monterey Water Revenue Adjustment Mechanism (“MWRAM”)
Regulatory Assets [Line Items]
Total regulatory assets, net in Condensed Consolidated Balance Sheets	12,162	10,864
Water Conservation Memorandum Account (“WCMA”)
Regulatory Assets [Line Items]
Total regulatory assets, net in Condensed Consolidated Balance Sheets	(7,683)	(5,039)
2022 General Rate Case Interim Memorandum Account
Regulatory Assets [Line Items]
Total regulatory assets, net in Condensed Consolidated Balance Sheets	9,513	20,650
Cost recovery balancing and memorandum accounts
Regulatory Assets [Line Items]
Total regulatory assets, net in Condensed Consolidated Balance Sheets	8,267	16,545
All other balancing and memorandum accounts
Regulatory Assets [Line Items]
Total regulatory assets, net in Condensed Consolidated Balance Sheets	4,344	2,749
Water Revenue Adjustment (“WRA”)
Regulatory Assets [Line Items]
Total regulatory assets, net in Condensed Consolidated Balance Sheets	(5,428)	(4,488)
Other, net
Regulatory Assets [Line Items]
Total regulatory assets, net in Condensed Consolidated Balance Sheets	$ 10,507	$ 9,739

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
-Topic 980
-SubTopic 340
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481878/980-340-50-1

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