Capitalized Interest - Summary of Interest Costs Incurred, Capitalized, Expensed and Charged to Cost of Sales (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Interest Costs Incurred Capitalized [Abstract]
Interest capitalized, beginning of period	$ 5,358	$ 4,271	$ 4,434	$ 4,072
Interest incurred	6,397	6,262	12,785	12,525
Interest expense	(4,814)	(5,956)	(9,902)	(11,874)
Interest charged to cost of sales	(2,365)	(245)	(2,741)	(391)
Interest capitalized, end of period	$ 4,576	$ 4,332	$ 4,576	$ 4,332