Note 5 - Recent Accounting Pronouncements (Details Textual) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	$ 410,000
Accounting Standards Update 2016-09 [Member]
Current Period Reclassification Adjustment	866,000
Accounting Standards Update 2016-09 [Member] | Additional Paid-in Capital [Member]
Current Period Reclassification Adjustment	(866,000)
Accounting Standards Update 2016-09 [Member] | Retained Earnings [Member]
Current Period Reclassification Adjustment	$ 866,000