Schedule of Total Revenue from Major Customers (Detail) - Customer Concentration Risk - Sales Revenue, Net	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Major Customer A
Revenue, Major Customer [Line Items]
Concentration risk percentage	10.70%	22.40%	13.10%
Major Customer B
Revenue, Major Customer [Line Items]
Concentration risk percentage	26.90%	29.90%	34.70%