Derivative Activities - Derivative Volumes Hedged and Average Hedge Prices (Parenthetical) (Detail) - 2023 Commodity Contract - Natural Gas	Mar. 31, 2022 MMBTU $ / MMBTU
Derivative [Line Items]
Volume Hedged \| MMBTU	100,000
Call Swaptions
Derivative [Line Items]
Weighted average price of hedge \| $ / MMBTU	3.21

Nominal number of units used to calculate payment on derivative.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 40
-Section 50
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

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