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Accrued Expenses And Other Long-term Liabilities - Additional Information (Detail) - Asset Retirement Obligation Costs [Member]
12 Months Ended
Dec. 31, 2019
USD ($)
Accrued Liabilities And Other Long Term Liabilities [Line Items]  
Property, Plant and Equipment, Useful Life 30 years
Asset retirement obligation, legally restricted assets, fair value $ 0