Capitalized Interest - Summary of Interest Costs Incurred, Capitalized, Expensed and Charged to Cost of Sales (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Interest Costs Incurred Capitalized [Abstract]
Interest capitalized, beginning of period	$ 4,576	$ 4,332	$ 4,434	$ 4,072
Interest incurred	6,562	6,317	19,347	18,842
Interest expense	(5,624)	(6,081)	(15,526)	(17,955)
Interest charged to cost of sales	(600)	(288)	(3,341)	(679)
Interest capitalized, end of period	$ 4,914	$ 4,280	$ 4,914	$ 4,280