Stockholders' Equity - Changes in Accumulated Other Comprehensive Income (Loss) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ 102
Other comprehensive income (loss) before reclassifications	1
Amounts reclassified from accumulated other comprehensive income (loss)	0
Net current period other comprehensive income (loss)	1
Ending Balance	103
Unrealized Gains and Losses on Available-for Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	1
Other comprehensive income (loss) before reclassifications	1
Amounts reclassified from accumulated other comprehensive income (loss)	0
Net current period other comprehensive income (loss)	1
Ending Balance	2
Foreign Currency Items [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	101
Other comprehensive income (loss) before reclassifications	0
Amounts reclassified from accumulated other comprehensive income (loss)	0
Net current period other comprehensive income (loss)	0
Ending Balance	$ 101