Note 10 - Stockholders' Deficiency and Additional Paid-in Capital (Details Textual) | Jan. 26, 2016shares | Nov. 12, 2015shares | Nov. 10, 2015shares | Aug. 14, 2015USD ($)$ / sharesshares | Aug. 13, 2015USD ($)$ / sharesshares | Jul. 30, 2015USD ($)$ / sharesshares | Apr. 22, 2015shares | Oct. 27, 2014USD ($)shares | Jul. 25, 2014USD ($)$ / sharesshares | Jan. 29, 2014USD ($)$ / sharesshares | Jul. 25, 2013USD ($)shares | Dec. 31, 2015USD ($)shares | Dec. 31, 2014USD ($)shares | May. 01, 2014shares | Dec. 31, 2013shares | Jun. 19, 2013shares |
Stock Option Plan 1999 [Member] | | | | | | | | | | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number | | | | | | | | | | | | 0 | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period | | | | | | | | | 36,000 | | | | | | | |
VBI US Stock Option Plan 2006 [Member] | | | | | | | | | | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number | | | | | | | | | | | | 2,624,368 | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period | | | | | | | | | | | | 100,541 | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant | | | | | | | | | | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period | | | | | | | | | | | | 0 | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | | | | | | | | | | | | 2,724,909 | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period | | | | | | | | | | | | 100,541 | | | | |
Stock Option Plan 1999, VBI US Stock Option Plan 2006, Stock Incentive Plan 2013 [Member] | | | | | | | | | | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant | | | | | | | | | 0 | | | | | | | |
Equity Incentive Plan 2014 [Member] | Increase Event [Member] | | | | | | | | | | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized | | | | | | | | | | | | 1,200,000 | | | | |
Equity Incentive Plan 2014 [Member] | Subsequent Event [Member] | | | | | | | | | | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized | 1,251,597 | | | | | | | | | | | | | | | |
Equity Incentive Plan 2014 [Member] | | | | | | | | | | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number | | | | | | | | | | | | 1,412,000 | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period | | | | | | | | | | | | 0 | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant | | | | | | | | | | | | 384,325 | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period | | | | | | | | | | | | 0 | 0 | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | | | | | | | | | | | | 1,816,326 | | 815,688 | | |
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period | | | | | | | | | | | | 20,001 | | | | |
Share-based Compensation Arrangement by Share-based Payment Award Percent of Additional Shares Authorized | | | | | | | | | | | | 5.00% | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares | | | | | | | | | | | | 2,440,668 | 1,927,696 | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value | $ | | | | | | | | | | | | | $ 88,009 | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value | $ | | | | | | | | | | | | $ 1,243,922 | 512,035 | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value | $ | | | | | | | | | | | | 557,830 | 3,201,180 | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value | $ | | | | | | | | | | | | $ 503,080 | $ 1,142,810 | | | |
Stock Incentive Plan 2013 [Member] | | | | | | | | | | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number | | | | | | | | | | | | 8,871 | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant | | | | | | | | | | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period | | | | | | | | | | | | 51,129 | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | | | | | | | | | | | | 300,000 | | | | 300,000 |
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period | | | | | | | | | | | | 240,000 | | | | |
Plan 2006 and 2014 [Member] | Vest in First Anniversary [Member] | | | | | | | | | | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage | | | | | | | | | | | | 25.00% | | | | |
Plan 2006 and 2014 [Member] | Vests on a Monthly Basis [Member] | | | | | | | | | | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage | | | | | | | | | | | | 2.083% | | | | |
Plan 2006 and 2014 [Member] | Vest After First Anniversary [Member] | | | | | | | | | | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period | | | | | | | | | | | | 3 years | | | | |
Plan 2006 and 2014 [Member] | Vest in Full [Member] | | | | | | | | | | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage | | | | | | | | | | | | 100.00% | | | | |
Plan 2006 and 2014 [Member] | | | | | | | | | | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period | | | | | | | | | | | | 4 years | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period | | | | | | | | | | | | 10 years | | | | |
Series 1 Convertible Preferred Stock [Member] | July 2013 PIPE [Member] | | | | | | | | | | | | | | | | |
Stock Issued During Period, Shares, New Issues | | | | | | | | | | | 2,711,880 | | | | | |
Series 1 Convertible Preferred Stock [Member] | | | | | | | | | | | | | | | | |
Stock Issued During Period, Shares, Conversion of Convertible Securities | | 2,001,682 | 2,001,682 | | | | | | | | | | | | | |
Conversion of Stock, Shares Converted | | 2,001,682 | 2,001,682 | | | | | | | | | | | | | |
Reverse Stock Split [Member] | | | | | | | | | | | | | | | | |
Stockholders' Equity Note, Stock Split, Conversion Ratio | | | | | | | | | 5 | | | | | | | |
Former Paulson Employees [Member] | | | | | | | | | | | | | | | | |
Stock Issued During Period, Shares, Restricted Stock Award, Gross | | | | | | | | | 20,001 | | | | | | | |
Stock Issued During Period, Value, Restricted Stock Award, Gross | $ | | | | | | | | | $ 85,000 | | | | | | | |
Consultants [Member] | | | | | | | | | | | | | | | | |
Stock Issued During Period, Shares, Issued for Services | | | | | | | | 275,000 | | | | | | | | |
Stock Issued During Period, Value, Issued for Services | $ | | | | | | | | $ 654,500 | | | | | | | | |
General and Administrative Expense [Member] | | | | | | | | | | | | | | | | |
Consulting Services Expense | $ | | | | | | $ 44,800 | | | | | | | | | | |
July 2013 PIPE [Member] | | | | | | | | | | | | | | | | |
Stock Issued During Period, Value, New Issues | $ | | | | | | | | | | | $ 5,250,000 | | | | | |
Stock Issued During Period, Shares, New Issues | | | | | | | | | | | 1,964,974 | | | | | |
January 2014 PIPE [Member] | Common Stock [Member] | | | | | | | | | | | | | | | | |
Stock Issued During Period, Shares, New Issues | | | | | | | | | | 100,000 | | | | | | |
July 2014 PIPE [Member] | | | | | | | | | | | | | | | | |
Stock Issued During Period, Value, New Issues | $ | | | | | | | | | $ 11,000,000 | | | | | | | |
Stock Issued During Period, Shares, New Issues | | | | | | | | | 5,128,061 | | | | | | | |
Share Price | $ / shares | | | | | | | | | $ 2.145 | | | | | | | |
Payments of Stock Issuance Costs | $ | | | | | | | | | $ 1,800,000 | | | | | | | |
Stock Issued | $ | | | | | | | | | $ 11 | | | | | | | |
Common Stock [Member] | Certain Operational Milestone [Member] | | | | | | | | | | | | | | | | |
Class of Warrant or Right, Number of Securities Called by Warrants or Rights | | | | | | | | | | | | 699,281 | | | | |
Common Stock [Member] | | | | | | | | | | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period | | | | | | | | | | | | | 41,016 | | | |
Stock Issued During Period, Shares, Conversion of Convertible Securities | | | | | | | | | | | | 2,001,682 | | | | |
Stock Issued During Period, Shares, Issued for Services | | | | | | | | | | | | 17,500 | 295,001 | | | |
Stock Issued During Period, Value, Issued for Services | $ | | | | | | | | | | | | $ 2 | $ 30 | | | |
Stock Issued During Period, Value, New Issues | $ | | | | | | | | | | | | $ 300 | $ 513 | | | |
Stock Issued During Period, Shares, New Issues | | | | | | | | | | | | 3,000,000 | 5,128,061 | | | |
Share Price | $ / shares | | | | | | | | | | $ 2.50 | | | | | | |
Proceeds from Issuance of Common Stock | $ | | | | | | | | | | $ 250,000 | | | | | | |
Class of Warrant or Right, Number of Securities Called by Warrants or Rights | | | | | | | | | 699,281 | | | | | | | |
Warrant [Member] | Certain Operational Milestone [Member] | | | | | | | | | | | | | | | | |
Proceeds from Other Equity | $ | | | | | | | | | | | | $ 3,000,000 | | | | |
Warrant [Member] | | | | | | | | | | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period | | | | | | | | | | | | | | | | |
Stock Issued During Period, Shares, Conversion of Convertible Securities | | | | | | | | | | | | | | | | |
Stock Issued During Period, Shares, Issued for Services | | | | | | | | | | | | | | | | |
Stock Issued During Period, Value, Issued for Services | $ | | | | | | | | | | | | | | | | |
Stock Issued During Period, Value, New Issues | $ | | | | | | | | | | | | | | | | |
Stock Issued During Period, Shares, New Issues | | | | | | | | | | | | | | | | |
Private Placement [Member] | | | | | | | | | | | | | | | | |
Proceeds from Issuance of Common Stock | $ | | | | $ 6,285,700 | | | | | | | | | | | | |
Securities Purchase Agreement, Number of Investors | | | | | 19 | | | | | | | | | | | |
Common stock, shares issued (in shares) | | | | | 3,000,000 | | | | | | | | | | | |
Shares Issued, Price per Share, Percentage of Volume Weighted Average Common Stock Price Reported by Bloomberg LP | | | | | 85.00% | | | | | | | | | | | |
Number of Trading Days Prior to Each Closing | | | | | 10 days | | | | | | | | | | | |
Private Placement, First Closing [Member] | | | | | | | | | | | | | | | | |
Shares Issued, Price Per Share | $ / shares | | | | | $ 2.10 | | | | | | | | | | | |
Proceeds from Issuance of Common Stock | $ | | | | | $ 4,798,500 | | | | | | | | | | | |
Common stock, shares issued (in shares) | | | | | 2,285,000 | | | | | | | | | | | |
Private Placement, Final Closing [Member] | | | | | | | | | | | | | | | | |
Shares Issued, Price Per Share | $ / shares | | | | $ 2.08 | | | | | | | | | | | | |
Proceeds from Issuance of Common Stock | $ | | | | $ 1,487,200 | | | | | | | | | | | | |
Common stock, shares issued (in shares) | | | | 715,000 | | | | | | | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number | | | | | | | | | | | | 4,045,239 | 2,797,239 | | 880,792 | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period | | | | | | | | | | | | | 41,016 | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant | | | | | | | | | | | | 384,325 | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period | | | | | | | | | | | | 51,129 | | | | |
Common Stock, Voting Rights, Percent | | | | | | | | | | | | 41.66% | | | | |
Stock Issued During Period, Shares, Issued for Services | | | | | | 17,500 | | | | | | | | | | |
Stock Issued During Period, Value, Issued for Services | $ | | | | | | | | | | | | $ 44,800 | $ 739,500 | | | |
Shares Issued, Price Per Share | $ / shares | | | | | | $ 2.56 | | | | | | | | | | |
Stock Issued During Period, Value, New Issues | $ | | | | | | | | | | | | 6,223,144 | 9,213,035 | | | |
Proceeds from Issuance of Common Stock | $ | | | | | | | | | | | | 6,285,700 | 15,214,561 | | | |
Payments of Stock Issuance Costs | $ | | | | | | | | | | | | $ 62,556 | $ 796,247 | | | |
Common stock, shares issued (in shares) | | | | | | | | | | | | 25,031,942 | 20,012,760 | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | | | | | | | | | | | | 4,841,235 | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period | | | | | | | | | | | | 360,542 | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized | | | | | | | 1,000,638 | | | | | | | | | |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized | $ | | | | | | | | | | | | $ 4,533,522 | | | | |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition | | | | | | | | | | | | 3 years | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term | | | | | | | | | | | | 8 years 36 days | | | | |
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares | | | | | | | | | $ 2.145 | | | | | | | |