Note 3 - Acquisition (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012 Thermonics [Member]	Jan. 16, 2012 Thermonics [Member]	Dec. 31, 2011 Thermonics [Member]
Business Acquisition, Cost of Acquired Entity, Purchase Price		$ 3,802		$ 3,802
Restructuring Charges		359	313
Business Acquisition, Cost of Acquired Entity, Transaction Costs				485	148
Business Acquisition, Purchase Price Allocation, Goodwill Amount		50		50
Revenues	$ 8,973	$ 10,731	$ 669