Regulatory Matters - Regulatory Assets, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Regulatory Assets [Line Items]
Regulatory assets	$ 142,153	$ 154,621
Less: current regulatory assets, net	2,841	2,629
Total regulatory assets, net, less current portion	139,312	151,992
Regulatory assets, net not earning a return	85,798	84,887
Income tax temporary differences, net
Regulatory Assets [Line Items]
Regulatory assets	25,946	22,420
Postretirement pensions and other postretirement benefits
Regulatory Assets [Line Items]
Regulatory assets	64,022	62,197
Business combinations debt premium, net
Regulatory Assets [Line Items]
Regulatory assets	18,667	19,937
Balancing and memorandum accounts, net
Regulatory Assets [Line Items]
Regulatory assets	24,772	38,334
Water Rate Adjustment
Regulatory Assets [Line Items]
Regulatory assets	(1,176)	2,588
Other, net
Regulatory Assets [Line Items]
Regulatory assets	$ 9,922	$ 9,145

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

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- 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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Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost.

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Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer.

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- Definition

Remaining balance of regulatory assets for which no return on investment during recovery is provided. In some cases, a regulator may permit an enterprise to include a cost that would be charged to expense by an unregulated enterprise as an allowable cost over a period of time by amortizing that cost for rate-making purposes, but the regulator does not include the unrecovered amount in the rate base.

+ References

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 https://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 340
-Section 55
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=123406419&loc=d3e44360-110383

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