Net Revenue by Geographical Location (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Revenue, Major Customer [Line Items]
Net revenue by geographical locations foreign									$ 36,695	$ 30,602	$ 21,677
Total government grants and cooperative agreements	0	0	0	91	527	1,479	0	436	91	2,442	1,432
Total revenue									36,786	33,044	23,109
FRANCE
Revenue, Major Customer [Line Items]
Net revenue by geographical locations foreign									7,321	7,385	4,432
SPAIN
Revenue, Major Customer [Line Items]
Net revenue by geographical locations foreign									7,061	6,504	4,175
CIS
Revenue, Major Customer [Line Items]
Net revenue by geographical locations foreign									8,016	3,754	3,383
BELGIUM
Revenue, Major Customer [Line Items]
Net revenue by geographical locations foreign									4,016	3,703	3,710
SWITZERLAND
Revenue, Major Customer [Line Items]
Net revenue by geographical locations foreign									3,866	3,315	1,330
Other Countries
Revenue, Major Customer [Line Items]
Net revenue by geographical locations foreign									6,415	5,941	4,647
UNITED STATES
Revenue, Major Customer [Line Items]
United States									$ 91	$ 2,442	$ 1,432