Balance Sheet Details - Available-for-Sale Securities Recorded at Fair Value with Unrealized Gains or Losses (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Amortized cost basis	$ 4,080	$ 2,881
Gross unrealized loss	(2)	(1)
Fair value	4,078	2,880
Corporate bonds and notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost basis		1,000
Gross unrealized loss		(1)
Fair value		999
Government securities/money market [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost basis	4,080	1,881
Gross unrealized loss	(2)
Fair value	$ 4,078	$ 1,881