Annual report pursuant to Section 13 and 15(d)

Fair Value Summary of Long-Term Debt with Fixed Interest Rates (Detail)

v3.10.0.1
Fair Value Summary of Long-Term Debt with Fixed Interest Rates (Detail) - USD ($)
$ in Thousands
Dec. 31, 2018
Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Long-term debt $ 511,375 $ 265,267