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Derivative Instruments - Additional Information (Detail) - Interest Rate Swap Agreements
12 Months Ended
Dec. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
Dec. 16, 2013
USD ($)
Derivative
Derivative Instruments, Gain (Loss) [Line Items]      
Interest rate swap inception date Dec. 31, 2015    
Number of forward-starting swap agreements | Derivative     3
Aggregated notional amount of interest swap agreements     $ 186,000,000
Derivative average Interest rate     2.73%
Derivative fixed Interest rate     5.23%
Interest rate swap effective date Dec. 31, 2015    
Interest rate swap expiration date Dec. 31, 2018    
Change in fair value of interest rate $ 1,100,000 $ 2,400,000  
Unrealized gains or losses included in accumulated other comprehensive income or loss 0    
Fair value of the interest rate swap liability $ 4,800,000 $ 6,600,000  
2013 Credit Facility      
Derivative Instruments, Gain (Loss) [Line Items]      
Interest rate swap inception date Dec. 16, 2013