Note 8 - Fair Value Measurements (Details Textual) - Foreign Exchange Contract [Member] - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Derivative Asset, Notional Amount	$ 7,200,000		$ 6,900,000
Other Current Liabilities [Member]
Derivative Liability, Current	100,000		$ 15,000
Other Nonoperating Income (Expense) [Member]
Derivative, Gain (Loss) on Derivative, Net	$ 100,000	$ 300,000