Derivatives and Hedging - Additional Information (Detail) CAD in Thousands		6 Months Ended	12 Months Ended
	Sep. 03, 2014 USD ($)	Jun. 30, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014	Jun. 30, 2016 CAD	Dec. 31, 2015 CAD
Derivative [Line Items]
Fair value interest rate swaps		$ (3,223,000)	$ (2,564,000)
Unfavorable change in fair value		659,000	(1,629,000)
2014 Swap No. 1 [Member]
Derivative [Line Items]
Term of derivative instrument	3 years
Notional amount of derivative instrument	$ 90,000,000
Effective date of agreement	Oct. 01, 2015
Termination date of derivative	Sep. 30, 2018
Fixed interest rate of Swap Agreement	2.20%
Derivative, Basis Spread on Variable Rate	3.50%
Derivative, Variable Interest Rate	5.70%
2014 Swap No. 2 [Member]
Derivative [Line Items]
Term of derivative instrument	3 years
Notional amount of derivative instrument	$ 40,000,000
Effective date of agreement	Oct. 01, 2015
Termination date of derivative	Sep. 30, 2018
Fixed interest rate of Swap Agreement	2.20%
Derivative, Basis Spread on Variable Rate	3.50%
Derivative, Variable Interest Rate	5.70%
2014 FX Contracts [Member]
Derivative [Line Items]
Fair value of derivative asset			$ 1,695,000
2014 FX Contracts [Member] | Minimum [Member]
Derivative [Line Items]
Termination date of derivative				Mar. 31, 2014
Forward exchange rate				1.0680
2014 FX Contracts [Member] | Maximum [Member]
Derivative [Line Items]
Termination date of derivative				Dec. 31, 2015
Forward exchange rate				1.1740
2015 FX Contracts [Member]
Derivative [Line Items]
Notional amount of derivative instrument | CAD					CAD 32,595	CAD 37,886
Fair value of derivative liability		$ (610,000)
2015 FX Contracts [Member] | Minimum [Member]
Derivative [Line Items]
Termination date of derivative		Apr. 30, 2016	Feb. 28, 2015
Forward exchange rate		1.2536	1.1384		1.2536	1.1384
2015 FX Contracts [Member] | Maximum [Member]
Derivative [Line Items]
Termination date of derivative		Apr. 30, 2017	Dec. 31, 2016
Forward exchange rate		1.3817	1.3831		1.3817	1.3831
Foreign Exchange Forward Contract [Member]
Derivative [Line Items]
Increase in other income		$ 2,305,000