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v3.23.1

Regulatory assets (Details) - USD ($) $ in Thousands | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2023 | Dec. 31, 2022 | Mar. 31, 2022
Regulatory Assets |  |  |
Regulatory Assets, Current | $ 216,318 | $ 165,092 | $ 89,078
Regulatory Assets, Noncurrent | 349,500 | 329,659 | 359,228
Total regulatory assets | 565,818 | 494,751 | 448,306
Regulatory assets not earning a rate of return | $ 255,600 | 242,500 | 268,100
Natural gas costs recoverable through rate adjustments |  |  |
Regulatory Assets |  |  |
Estimated Recovery or Refund Period as of March 31, 2023 | Up to 1 year |  |
Regulatory Assets, Current | $ 198,166 | 141,306 | 66,132
Conservation programs |  |  |
Regulatory Assets |  |  |
Estimated Recovery or Refund Period as of March 31, 2023 | Up to 1 year |  |
Regulatory Assets, Current | $ 8,599 | 8,544 | 7,567
Cost recovery mechanisms |  |  |
Regulatory Assets |  |  |
Regulatory Assets, Current | 3,954 | 4,019 | 3,432
Regulatory Assets, Noncurrent | $ 65,732 | 67,171 | 67,989
Cost recovery mechanisms | Minimum [Member] |  |  |
Regulatory Assets |  |  |
Estimated Recovery or Refund Period as of March 31, 2023 | Up to 1 year |  |
Cost recovery mechanisms | Maximum [Member] |  |  |
Regulatory Assets |  |  |
Estimated Recovery or Refund Period as of March 31, 2023 | Up to 10 years |  |
Other regulatory assets |  |  |
Regulatory Assets |  |  |
Regulatory Assets, Current | $ 5,599 | 11,223 | 11,947
Regulatory Assets, Noncurrent | $ 11,430 | 11,010 | 13,564
Other regulatory assets | Minimum [Member] |  |  |
Regulatory Assets |  |  |
Estimated Recovery or Refund Period as of March 31, 2023 | Up to 1 year |  |
Other regulatory assets | Maximum [Member] |  |  |
Regulatory Assets |  |  |
Estimated Recovery or Refund Period as of March 31, 2023 | Up to 16 years |  |
Pension and postretirement benefits |  |  |
Regulatory Assets |  |  |
Estimated Recovery or Refund Period as of March 31, 2023 | ** |  |
Regulatory Assets, Noncurrent | $ 143,349 | 143,349 | 142,681
Plant costs/asset retirement obligations |  |  |
Regulatory Assets |  |  |
Estimated Recovery or Refund Period as of March 31, 2023 | Over plant lives |  |
Regulatory Assets, Noncurrent | $ 44,131 | 44,462 | 63,325
Manufactured gas plant site remediation |  |  |
Regulatory Assets |  |  |
Estimated Recovery or Refund Period as of March 31, 2023 | - |  |
Regulatory Assets, Noncurrent | $ 26,605 | 26,624 | 26,089
Environmental compliance programs |  |  |
Regulatory Assets |  |  |
Estimated Recovery or Refund Period as of March 31, 2023 | - |  |
Regulatory Assets, Noncurrent | $ 21,942 | 0 | 0
Plant to be retired |  |  |
Regulatory Assets |  |  |
Estimated Recovery or Refund Period as of March 31, 2023 | - |  |
Regulatory Assets, Noncurrent | $ 21,072 | 21,525 | 29,452
Taxes recoverable from customers |  |  |
Regulatory Assets |  |  |
Estimated Recovery or Refund Period as of March 31, 2023 | Over plant lives |  |
Regulatory Assets, Noncurrent | $ 12,198 | 12,330 | 12,492
Long-term debt refinancing costs |  |  |
Regulatory Assets |  |  |
Estimated Recovery or Refund Period as of March 31, 2023 | Up to 37 years |  |
Regulatory Assets, Noncurrent | $ 3,041 | $ 3,188 | $ 3,636

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- Definition Describes the continual or periodic assessment of the probability of future recovery of regulatory assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 980 -SubTopic 340 -Name Accounting Standards Codification -Section 25 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482000/980-340-25-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 40 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481938/980-340-40-1 + Details
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- Definition 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. + References 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 + Details
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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 -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 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 55 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481849/980-340-55-2 + Details
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