Segment Information - Summary of Revenues on Percentage Basis by Geographic Regions (Detail)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Segment Reporting Information [Line Items]
Revenues on a percentage basis by geographic regions, based on the region	100.00%	100.00%
United States [Member]
Segment Reporting Information [Line Items]
Revenues on a percentage basis by geographic regions, based on the region	65.00%	60.00%
South America [Member]
Segment Reporting Information [Line Items]
Revenues on a percentage basis by geographic regions, based on the region	10.00%	12.00%
Japan [Member]
Segment Reporting Information [Line Items]
Revenues on a percentage basis by geographic regions, based on the region	3.00%	5.00%
Europe [Member]
Segment Reporting Information [Line Items]
Revenues on a percentage basis by geographic regions, based on the region	16.00%	20.00%
Other [Member]
Segment Reporting Information [Line Items]
Revenues on a percentage basis by geographic regions, based on the region	6.00%	3.00%