XML 82 R69.htm IDEA: XBRL DOCUMENT v3.19.1
Asset Impairments - Additional Information (Detail) - USD ($)
3 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Asset Impairment Charges [Abstract]    
Asset impairments $ 0 $ 6,186,000 [1]
[1] Refer to Note (14) for additional information regarding asset impairment charges.