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Percentage of subsidiary's or equity investee's stock sold in the stock transaction.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Note 1 - Background and Significant Accounting Policies (Details Textual) - USD ($)		9 Months Ended		12 Months Ended
	Nov. 15, 2019	Dec. 31, 2019	Dec. 31, 2018	Mar. 31, 2019	Nov. 30, 2019	Apr. 01, 2019
Impairment of Long-Lived Assets Held-for-use				$ 0
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		158,728,095	108,999,521
Operating Lease, Right-of-Use Asset		$ 144,146
Operating Lease, Liability, Total		$ 161,136
Accounting Standards Update 2016-02 [Member]
Operating Lease, Right-of-Use Asset						$ 182,624
Operating Lease, Liability, Total						$ 190,173
GB Sciences Louisiana, LLC [Member]
Disposal Group, Including Discontinued Operation, Consideration					$ 8,000,000
Earnout Payments	$ 8,000,000				$ 8,000,000
GB Sciences, Nevada, LLC and GB Sciences Las Vegas, LLC [Member]
Sale of Stock, Percentage of Ownership	75.00%
Sale of Stock, Consideration Received on Transaction	$ 3,000,000
Sale of Stock, Additional Earn-out Payments	$ 3,000,000
GB Sciences, Nevada, LLC and GB Sciences Las Vegas, LLC [Member]
Controlling Interest, Ownership Percentage by Parent		100.00%