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Accounting for Derivative Instruments and Hedging Activities - Additional Information (Detail) - USD ($)
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Natural Gas Contracts [Member]    
Derivative [Line Items]    
Maximum length of time hedging in future cash flow Nov. 30, 2018  
Natural Gas Storage and Transportation [Member]    
Derivative [Line Items]    
Derivative assets $ 0 $ 0
Derivative liabilities $ 0 $ 0