Note 5 - Fair Value Measurements and Financial Instruments (Details Textual) - USD ($)	Jun. 30, 2018	Dec. 31, 2017
Payment in Kind (PIK) Note [Member] \| Fair Value, Inputs, Level 3 [Member]
Convertible Debt, Fair Value Disclosures	$ 12,842,158	$ 11,395,208

Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

No definition available.

Name:	us-gaap_ConvertibleDebtFairValueDisclosures
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant