Quarterly report pursuant to Section 13 or 15(d)

Financial Instruments - Summary of Company's Long-Term Debt Instruments at their Carrying Value and Fair Value (Detail)

v3.21.2
Financial Instruments - Summary of Company's Long-Term Debt Instruments at their Carrying Value and Fair Value (Detail) - USD ($)
$ in Thousands
Sep. 30, 2021
Dec. 31, 2020
Debt Instrument [Line Items]    
Carrying value $ 191,867 $ 171,175
Fair value 231,971 189,363
Unsecured Debentures    
Debt Instrument [Line Items]    
Carrying value 56,591 54,905
Fair value 61,694 53,830
Secured Notes    
Debt Instrument [Line Items]    
Carrying value 133,954 115,350
Fair value 169,259 134,609
Other Long Term Debt    
Debt Instrument [Line Items]    
Carrying value 1,322 920
Fair value $ 1,018 $ 924