Accumulated Other Comprehensive Loss (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Increase (Decrease) in Accumulated Other Comprehensive Loss [Roll Forward]
Balance at beginning of period			$ 72,301
Balance at end of period	70,221		72,301
Foreign currency translation
Increase (Decrease) in Accumulated Other Comprehensive Loss [Roll Forward]
Balance at beginning of period	(471)	18
Total other comprehensive (loss) income	(161)	(509)
Balance at end of period	(632)	(491)
Available-for-sale marketable securities
Increase (Decrease) in Accumulated Other Comprehensive Loss [Roll Forward]
Balance at beginning of period	23	19
Other comprehensive (loss) income	0	46
Deferred income taxes	0	(18)
Total other comprehensive (loss) income	0	28
Balance at end of period	23	47
Total accumulated other comprehensive loss
Increase (Decrease) in Accumulated Other Comprehensive Loss [Roll Forward]
Balance at end of period	$ (609)	$ (444)