Long Lived Assets by Geographical Location (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Long-Lived Assets by Geographical Areas [Line Items]
Total long-lived assets	$ 4,923	$ 3,533
UNITED STATES
Long-Lived Assets by Geographical Areas [Line Items]
Total long-lived assets	4,624	3,088
Europe And Other
Long-Lived Assets by Geographical Areas [Line Items]
Total long-lived assets	$ 299	$ 445