Annual report pursuant to Section 13 and 15(d)

Fair Value Measurements - Assets and Liabilities Carried at Fair Value Measured on Recurring Basis (Detail)

v3.8.0.1
Fair Value Measurements - Assets and Liabilities Carried at Fair Value Measured on Recurring Basis (Detail) - USD ($)
$ in Thousands
Dec. 31, 2017
Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair value of interest rate swap agreements, asset $ 205  
Interest rate swaps, Liability   $ (13,015)
Interest Rate Swap [Member] | Fair Value, Measurements, Recurring [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair value of interest rate swap agreements, asset 205  
Interest rate swaps, Liability   (13,015)
Interest Rate Swap [Member] | Level 2 [Member] | Fair Value, Measurements, Recurring [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair value of interest rate swap agreements, asset $ 205  
Interest rate swaps, Liability   $ (13,015)