Note 2 - Summary of Significant Accounting Policies (Details Textual)			1 Months Ended	2 Months Ended	3 Months Ended								12 Months Ended
	Oct. 27, 2014 USD ($) $ / shares shares	Oct. 06, 2014	Oct. 31, 2014 USD ($) shares	Dec. 31, 2015 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2015 USD ($) shares	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
IPO [Member] | Underwriters [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period | shares	916,500
IPO [Member]
Stock Issued During Period, Shares, New Issues | shares	7,026,500		7,026,500
Share Price | $ / shares	$ 10
Proceeds from Issuance Initial Public Offering	$ 62,500,000		$ 62,500,000
Payments of Stock Issuance Costs	$ 7,800,000
Conversion of Stock, Shares Converted | shares	8,651,805
Reverse Stock Split [Member]
Stockholders' Equity Note, Stock Split, Conversion Ratio		15.87
Available-for-sale Securities, Gross Realized Gain (Loss)													$ 0	$ 0	$ 0
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities													0	0	$ 0
Liability for Uncertain Tax Positions, Current				$ 0	$ 0				$ 0				$ 0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period | shares													45,413
Proceeds from Issuance Initial Public Offering														62,485,000
Payments of Stock Issuance Costs														452,000
Maximum Value of Stock Offered for Sale				40,000,000
Number of Operating Segments													1
Number of Reportable Segments													1
Deferred Finance Costs, Gross				$ 100,000	$ 100,000								$ 100,000
Revenues										$ 2,948,000				$ 2,948,000