Note 12 - Fair Value Measurements - Schedule of Carrying Value and Fair Value by Fair Value Hierarchy of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Fair Value, Measurements, Recurring [Member]
Liabilities, fair value	$ 3,840	$ 7,175
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Liabilities, fair value
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Liabilities, fair value
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Liabilities, fair value	3,840	7,175
Fair Value, Measurements, Recurring [Member] | Warrant [Member]
Liabilities, fair value	1,474	1,951
Fair Value, Measurements, Recurring [Member] | Warrant [Member] | Fair Value, Inputs, Level 1 [Member]
Liabilities, fair value
Fair Value, Measurements, Recurring [Member] | Warrant [Member] | Fair Value, Inputs, Level 2 [Member]
Liabilities, fair value
Fair Value, Measurements, Recurring [Member] | Warrant [Member] | Fair Value, Inputs, Level 3 [Member]
Liabilities, fair value	1,474	1,951
Fair Value, Measurements, Recurring [Member] | Embedded Derivative [Member]
Liabilities, fair value	2,366	5,224
Fair Value, Measurements, Recurring [Member] | Embedded Derivative [Member] | Fair Value, Inputs, Level 1 [Member]
Liabilities, fair value
Fair Value, Measurements, Recurring [Member] | Embedded Derivative [Member] | Fair Value, Inputs, Level 2 [Member]
Liabilities, fair value
Fair Value, Measurements, Recurring [Member] | Embedded Derivative [Member] | Fair Value, Inputs, Level 3 [Member]
Liabilities, fair value	2,366	5,224
Fair Value, Measurements, Nonrecurring [Member]
Assets, fair value	1,835	1,916
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, fair value	33	189
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, fair value	1,802	1,727
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, fair value
Fair Value, Measurements, Nonrecurring [Member] | Corn and Finished Goods Inventory [Member]
Assets, fair value	1,835	1,916
Fair Value, Measurements, Nonrecurring [Member] | Corn and Finished Goods Inventory [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, fair value	33	189
Fair Value, Measurements, Nonrecurring [Member] | Corn and Finished Goods Inventory [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, fair value	1,802	1,727
Fair Value, Measurements, Nonrecurring [Member] | Corn and Finished Goods Inventory [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, fair value