Segment Information - Summary of Revenues on Percentage Basis by Geographic Regions (Detail)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Segment Information [Line Items]
Revenues on a percentage basis by geographic regions, based on the country	100.00%	100.00%
United States [Member]
Segment Information [Line Items]
Revenues on a percentage basis by geographic regions, based on the country	80.00%	87.00%
Japan [Member]
Segment Information [Line Items]
Revenues on a percentage basis by geographic regions, based on the country	6.00%	9.00%
Europe [Member]
Segment Information [Line Items]
Revenues on a percentage basis by geographic regions, based on the country	9.00%	3.00%
Other [Member]
Segment Information [Line Items]
Revenues on a percentage basis by geographic regions, based on the country	5.00%	1.00%