Quarterly report pursuant to Section 13 or 15(d)

Accumulated Other Comprehensive Income (Loss) - Summary of Changes in Accumulated Other Comprehensive Income (Loss) (Detail)

v3.8.0.1
Accumulated Other Comprehensive Income (Loss) - Summary of Changes in Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Beginning Balance     $ 725,164  
Other comprehensive income (loss) before reclassifications     27  
Amounts reclassified out of accumulated other comprehensive income (loss)     1,765  
Other comprehensive income (loss) $ 463 $ 2,602 1,792 $ (2,157)
Ending Balance 722,974   722,974  
Gains and Losses on Cash Flow Hedges [Member]        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Beginning Balance     (2,085)  
Other comprehensive income (loss) before reclassifications     27  
Amounts reclassified out of accumulated other comprehensive income (loss)     1,765  
Other comprehensive income (loss)     1,792  
Ending Balance (293)   (293)  
Defined Benefit Pension Plan [Member]        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Beginning Balance     (177)  
Ending Balance (177)   (177)  
Accumulated Other Comprehensive Income (Loss) [Member]        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Beginning Balance     (2,262)  
Ending Balance $ (470)   $ (470)