Major Customers and Geographic Information (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Sales by geographical region
Net sales	$ 6,897	$ 7,242	$ 6,936	$ 6,506	$ 5,986	$ 6,706	$ 5,989	$ 5,950	$ 27,581	$ 24,631	$ 16,827
Net sales (as a percent)	100.00%				100.00%				100.00%	100.00%	100.00%
United States
Sales by geographical region
Net sales									17,386	16,430	9,809
Net sales (as a percent)	63.00%				67.00%				63.00%	67.00%	58.00%
Germany
Sales by geographical region
Net sales									1,342	1,223	1,192
Net sales (as a percent)	5.00%				5.00%				5.00%	5.00%	7.00%
The Netherlands
Sales by geographical region
Net sales									1,207	953	1,118
Net sales (as a percent)	4.00%				4.00%				4.00%	4.00%	7.00%
Other
Sales by geographical region
Net sales									$ 7,646	$ 6,025	$ 4,708
Net sales (as a percent)	28.00%				24.00%				28.00%	24.00%	28.00%