Derivative Instruments - Additional Information (Detail) - Interest Rate Swap Agreements	12 Months Ended
	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 16, 2013 USD ($) Derivative
Derivative Instruments, Gain (Loss) [Line Items]
Interest rate swap inception date	Dec. 16, 2013
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	$ (2,000,000)	$ (2,400,000)
Unrealized gains or losses included in accumulated other comprehensive income or loss	0
Fair value of the interest rate swap liability	$ 6,600,000	$ 3,400,000