Inventories - Components of Inventories (Detail) (USD $)
In Thousands, unless otherwise specified
Mar. 31, 2015
Dec. 31, 2014
Schedule of Inventory [Line Items]    
Raw materials $ 1,616 $ 853
Work-in-process 0 254
Finished goods 18,449 11,992
Total inventories $ 20,065 $ 13,099