Note 10 - Stock-based Compensation and Incentive Plans - Nonvested Restricted Stock Units Activity (Details) - Phantom Stock Plan [Member] - $ / shares	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Series A Warrants [Member]
Balance (in dollars per share)	$ 1.00	$ 1.00
Balance (in shares)	7,650	21,934
Vested (in dollars per share)	$ 1.00	$ 1.00
Vested (in shares)	(7,650)	(13,009)
Cancelled/forfeited (in dollars per share)		$ 1.00
Cancelled/forfeited (in shares)		(1,275)
Balance (in dollars per share)	$ 0	$ 1.00
Balance (in shares)	0	7,650
Series B Warrants [Member]
Balance (in dollars per share)	$ 2.94	$ 0.98
Balance (in shares)	8,269	23,712
Vested (in dollars per share)	$ 2.94	$ 0.98
Vested (in shares)	(8,269)	(14,064)
Cancelled/forfeited (in dollars per share)		$ 0.98
Cancelled/forfeited (in shares)		(1,379)
Balance (in dollars per share)	$ 0	$ 2.94
Balance (in shares)	0	8,269
Time Based Restricted Stock Awards [Member]
Balance (in dollars per share)	$ 226.50	$ 308.24
Balance (in shares)	4,517	13,526
Vested (in dollars per share)	$ 226.50	$ 360.14
Vested (in shares)	(4,517)	(8,223)
Cancelled/forfeited (in dollars per share)		$ 240.39
Cancelled/forfeited (in shares)		(786)
Balance (in dollars per share)	$ 0	$ 226.50
Balance (in shares)	0	4,517

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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-Publisher FASB
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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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