Note 13 - Fair Value Measurements - Schedule of Carrying Value and Fair Value by Fair Value Hierarchy of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Fair Value, Recurring [Member] | Embedded Derivative [Member]
Derivative liability, fair value	$ 29
Fair Value, Recurring [Member] | Embedded Derivative [Member] | Fair Value, Inputs, Level 1 [Member]
Derivative liability, fair value
Fair Value, Recurring [Member] | Embedded Derivative [Member] | Fair Value, Inputs, Level 2 [Member]
Derivative liability, fair value
Fair Value, Recurring [Member] | Embedded Derivative [Member] | Fair Value, Inputs, Level 3 [Member]
Derivative liability, fair value	29
Fair Value, Recurring [Member] | Warrant [Member]
Derivative liability, fair value		$ 8
Fair Value, Recurring [Member] | Warrant [Member] | Fair Value, Inputs, Level 1 [Member]
Derivative liability, fair value
Fair Value, Recurring [Member] | Warrant [Member] | Fair Value, Inputs, Level 2 [Member]
Derivative liability, fair value
Fair Value, Recurring [Member] | Warrant [Member] | Fair Value, Inputs, Level 3 [Member]
Derivative liability, fair value		8
Fair Value, Nonrecurring [Member] | Corn and Finished Goods Inventory [Member]
Corn and finished goods inventory, fair value	599	940
Fair Value, Nonrecurring [Member] | Corn and Finished Goods Inventory [Member] | Fair Value, Inputs, Level 1 [Member]
Corn and finished goods inventory, fair value		267
Fair Value, Nonrecurring [Member] | Corn and Finished Goods Inventory [Member] | Fair Value, Inputs, Level 2 [Member]
Corn and finished goods inventory, fair value	599	673
Fair Value, Nonrecurring [Member] | Corn and Finished Goods Inventory [Member] | Fair Value, Inputs, Level 3 [Member]
Corn and finished goods inventory, fair value