Note 14 - Stockholders' Equity - Summary of Non-vested Restricted Stock Units (Details) - Restricted Stock Units (RSUs) [Member] - USD ($)	1 Months Ended	12 Months Ended
	Feb. 28, 2019	Sep. 30, 2020	Sep. 30, 2019
Non-Vested restricted stock units (in shares)		3,318,640	2,207,242
Non-Vested restricted stock units, weighted average grant date fair value		$ 10,006,000	$ 7,302,000
Granted (in shares)	265,960	904,616	1,810,017
Granted, weighted average grant date fair value		$ 2,188,000	$ 5,400,000
Vested (in shares)		(663,736)	(563,711)
Vested, weighted average grant date fair value		$ (2,357,000)	$ (2,261,000)
Forfeited (in shares)		(61,205)	(134,908)
Forfeited, weighted average grant date fair value		$ (142,000)	$ (435,000)
Non-Vested restricted stock units (in shares)		3,498,315	3,318,640
Non-Vested restricted stock units, weighted average grant date fair value		$ 9,695,000	$ 10,006,000