Segment Information - Summary of Revenue by Geographic Region (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 14,268	$ 8,307
China [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	6,450	959
Taiwan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	3,764	39
Korea [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	1,896	570
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	1,370	915
Australia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue		5,406
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 788	$ 418