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Components of Energy Supply Obligations (Detail) - USD ($) $ in Millions | Jun. 30, 2022 | Dec. 31, 2021 | Jun. 30, 2021
--- | --- | --- | ---
Contractual Obligation [Line Items] |  |  |
Energy Supply Obligations-Current | $ 16.6 | $ 14.5 | $ 9.9
Exchange Gas Obligation |  |  |
Contractual Obligation [Line Items] |  |  |
Energy Supply Obligations-Current | 12.5 | 6.7 | 4.8
Renewable Energy Portfolio Standards |  |  |
Contractual Obligation [Line Items] |  |  |
Energy Supply Obligations-Current | 4.1 | $ 7.8 | 5.0
Power Supply Contract Divestitures |  |  |
Contractual Obligation [Line Items] |  |  |
Energy Supply Obligations-Current | $ 0.0 |  | $ 0.1

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- Definition Current liabilities attributable to energy marketing activities (trading activities). Current energy marketing (trading activities) are when entities engage in both financial and physical trading to increase profits, manage their commodity price risk and enhance system reliability. They may trade electricity, coal, natural gas and oil. These entities typically use a variety of financial instruments, including forward contracts, options and swaps. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.20) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Definition Contractual Obligation [Line Items] + References No definition available. + Details
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