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Asset Impairments - Additional Information (Detail) - USD ($)
3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Asset Impairment Charges [Abstract]        
Asset impairments $ 0 $ 1,215,000 [1] $ 0 $ 7,401,000 [1]
[1] Refer to Note (14) for additional information regarding asset impairment charges.