Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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Note 12 - Stock-based Compensation - Issuance of Stock Options (Details) - $ / shares																																								12 Months Ended
	Dec. 31, 2020	Dec. 24, 2020	Nov. 17, 2020	Nov. 12, 2020	Oct. 29, 2020	Oct. 20, 2020	Oct. 15, 2020	Oct. 01, 2020	Sep. 29, 2020	Sep. 25, 2020	Aug. 25, 2020	Aug. 19, 2020	Aug. 14, 2020	Aug. 02, 2020	Jul. 31, 2020	Jul. 20, 2020	Jul. 09, 2020	Jun. 16, 2020	Jun. 11, 2020	May 07, 2020	May 05, 2020	Apr. 21, 2020	Mar. 14, 2020	Mar. 01, 2020	Feb. 25, 2020	Jan. 23, 2020	Sep. 16, 2019	Aug. 19, 2019	Aug. 14, 2019	Aug. 13, 2019	Jul. 14, 2019	Jun. 16, 2019	May 23, 2019	May 04, 2019	Mar. 29, 2019	Mar. 15, 2019	Mar. 08, 2019	Feb. 24, 2019	Jan. 10, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Number of Options, Options Outstanding (in shares)	39,604,515																																							39,604,515	7,040,265	422,044
Weighted Avg Exercise Price, Options Outstanding (in dollars per share)	$ 0.36																																							$ 0.36	$ 1.28	$ 1.95
Number of Options, Options Granted (in shares)	27,560,000					40,000		300,000	300,000		40,000						175,000	2,000,000					5,056,000				500,000	500,000											5,995,000	35,471,000	7,495,000
Weighted Avg Exercise Price, Options Granted (in dollars per share)	$ 0.23					$ 0.09		$ 0.11	$ 0.11		$ 0.13						$ 0.18	$ 0.19					$ 0.19				$ 0.43	$ 0.26											$ 1.52	$ 0.23
Number of Options, Options Expired (in shares)																													(387,004)			(40,000)	(10,000)					(35,000)
Weighted Avg Exercise Price, Options Expired (in dollars per share)																													$ 2.11			$ 1.52	$ 1.52					$ 1.15
Number of Options, Options Exercised (in shares)																																			(65,789)	(164,473)	(164,473)			0	(394,735)
Weighted Avg Exercise Price, Options Exercised (in dollars per share)																																			$ 1.52	$ 1.52	$ 1.52
Number of Options, Options Cancelled (in shares)		(12,500)	(25,125)	(225,000)	(1,250)		(56,250)			(37,500)		(75,375)	(675,000)	(10,000)	(3,750)	(400,000)			(15,000)	(15,000)	(30,000)	(150,000)		(50,000)	(5,000)	(50,000)				(5,000)	(5,000)			(15,000)
Weighted Avg Exercise Price, Options Cancelled (in dollars per share)		$ 0.19	$ 0.19	$ 0.19	$ 0.19		$ 0.19			$ 0.19		$ 0.19	$ 0.19	$ 1.52	$ 0.19	$ 1.52			$ 1.52	$ 1.52	$ 1.52	$ 0.19		$ 1.52	$ 1.12	$ 1.52				$ 1.52	$ 1.52			$ 0.19
Number of Options, Options Vested (in shares)	14,624,140																																							14,624,140
Weighted Avg Exercise Price, Vested (in dollars per share)	$ 0.59																																							$ 0.59
Options 2 [Member]
Number of Options, Options Granted (in shares)																												100,000
Weighted Avg Exercise Price, Options Granted (in dollars per share)																												$ 0.35
Number of Options, Options Cancelled (in shares)			(50,000)	(950,000)										(5,000)		(50,000)
Weighted Avg Exercise Price, Options Cancelled (in dollars per share)			$ 1.52	$ 1.52										$ 0.19		$ 0.19
Options 3 [Member]
Number of Options, Options Granted (in shares)																												100,000
Weighted Avg Exercise Price, Options Granted (in dollars per share)																												$ 0.45
Options 4 [Member]
Number of Options, Options Granted (in shares)																												100,000
Weighted Avg Exercise Price, Options Granted (in dollars per share)																												$ 0.55
Option 5 [Member]
Number of Options, Options Granted (in shares)																												100,000
Weighted Avg Exercise Price, Options Granted (in dollars per share)																												$ 0.65
Option 6 [Member]
Number of Options, Options Granted (in shares)																												100,000
Weighted Avg Exercise Price, Options Granted (in dollars per share)																												$ 0.75