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Regulatory Matters: Winter Storm Uri (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2022 | Dec. 31, 2021 | Mar. 31, 2021
Public Utilities, General Disclosures [Line Items] |  |  |
Regulatory assets | $ 723,344 | $ 796,599 |
Winter Storm Uri Incremental Costs in a Separately Tracked Mechanism |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Regulatory assets | 438,675 | 509,025 |
Winter Storm Uri |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Amount Recovered Through Regulatory Mechanism | $ 73,000 |  |
Winter Storm Uri | Winter Storm Uri Incremental Costs in a Separately Tracked Mechanism |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Regulatory assets |  | $ 546,000 |
Regulatory Asset, Amortization Period | 3 years 1 month 6 days | 3 years 6 months |
Winter Storm Uri | Carrrying Costs |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Regulatory assets | $ 2,300 |  | $ 0

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- Definition The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period. + 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 http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
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