Note 3 - Goodwill, Intangible and Long-lived Assets (Details) - Estimated Useful Lives of Finite Lived Intangible Assets	12 Months Ended
	Dec. 31, 2014
Customer Relationships [Member] | Sigma [Member]
Finite-lived intangible assets resulting from the acquisition of Sigma:
Estimated life	72 months
Customer Relationships [Member] | Thermonics [Member]
Finite-lived intangible assets resulting from the acquisition of Sigma:
Estimated life	72 months
Remaining estimated life	36 months 15 days
Computer Software, Intangible Asset [Member] | Sigma [Member]
Finite-lived intangible assets resulting from the acquisition of Sigma:
Estimated life	120 months
Remaining estimated life	45 months
Patented Technology [Member] | Sigma [Member]
Finite-lived intangible assets resulting from the acquisition of Sigma:
Estimated life	60 months
Patented Technology [Member] | Thermonics [Member]
Finite-lived intangible assets resulting from the acquisition of Sigma:
Estimated life	132 months
Remaining estimated life	96 months 15 days
Order or Production Backlog [Member] | Thermonics [Member]
Finite-lived intangible assets resulting from the acquisition of Sigma:
Estimated life	3 months
Trade Names [Member] | Thermonics [Member]
Finite-lived intangible assets resulting from the acquisition of Sigma:
Estimated life	48 months
Remaining estimated life	12 months 15 days
Noncompete Agreements [Member] | Thermonics [Member]
Finite-lived intangible assets resulting from the acquisition of Sigma:
Estimated life	18 months