Note 13 - Long-term Incentive Plan - Activity Pertaining to Phantom and Restricted Common Stock Unit Awards (Details) - Long-Term Incentive Plan [Member] - Phantom and Restricted Units Holders [Member]	12 Months Ended
	Dec. 31, 2021 $ / shares shares
Nonvested, number of units, beginning balance (in shares) | shares	1,350,366
Nonvested, weighted average grant date fair value, beginning balance (in dollars per share) | $ / shares	$ 1.81
Granted, number of units (in shares) | shares	574,406
Granted, weighted average grant date fair value (in dollars per share) | $ / shares	$ 2.75
Vested, number of units (in shares) | shares	369,482
Vested, weighted average grant date fair value (in dollars per share) | $ / shares	$ 4.00
Forfeited, number of units (in shares) | shares	0
Forfeited, weighted average grant date fair value (in dollars per share) | $ / shares	$ 0
Nonvested, number of units, ending balance (in shares) | shares	1,555,290
Nonvested, weighted average grant date fair value, ending balance (in dollars per share) | $ / shares	$ 1.66