XML 53 R51.htm IDEA: XBRL DOCUMENT v3.20.1
Commitments and Contingencies - Additional Information (Detail) - USD ($)
Mar. 31, 2020
Dec. 31, 2019
Commitments And Contingencies Disclosure [Abstract]    
Estimated remediation liabilities included in accrued liabilities $ 600,000 $ 700,000
Estimated remediation liabilities included in other noncurrent liabilities 2,300,000 2,100,000
Accrued liabilities for legal contingencies $ 0 $ 0