Note 9 - Capital and Other Components of Equity (Details Textual) $ / shares in Units, $ in Thousands				3 Months Ended		6 Months Ended
	Sep. 25, 2023 USD ($) $ / shares shares	Sep. 24, 2023 $ / shares shares	Jun. 29, 2020 USD ($) shares	Sep. 30, 2023 USD ($) Vote $ / shares shares	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) Vote $ / shares shares	Sep. 30, 2023 Vote $ / shares $ / shares shares	Sep. 30, 2022 USD ($) $ / shares shares	Jun. 30, 2023 $ / shares shares	Mar. 31, 2023 shares
Common Stock, Shares, Issued		1,951,371
At-the-market Sales Agreement, Common Stock, Maximum Amount | $			$ 75,000
Fair Value Adjustment of Warrants | $				$ 1,826	$ (0)	$ 1,826		$ (10)
At-the-market Sales Agreement, Underwriter Fees, Percentage of Sales			3.00%
Class of Warrant or Right, Exercise Price of Warrants or Rights (in CAD per share) | $ / shares	$ 0.64			$ 1.36		$ 1.36	$ 1.36
Warrants Issued in May 2018 [Member]
Class of Warrant or Right, Outstanding									137,370
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)									1
Class of Warrant or Right, Exercise Price of Warrants or Rights (in CAD per share) | $ / shares									$ 62.88
At-the-market Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)			0			0		54,108
Proceeds from Issuance of Common Stock, Net | $								$ 304
Sale of Stock, Average Price Per Share (in dollars per share) | $ / shares								$ 5.7
Other Selling, General and Administrative Expense | $								$ 10
Private Placement [Member]
Stock Issued During Period, Shares, New Issues (in shares)		1,951,371
Proceeds from Issuance of Common Stock, Net | $	$ 7,300
Purchase Agreement [Member]
Stock Issued Warrents Exercisable	4,643,244
Common Warrant and Pre-Funded Warrant [Member]
Sale of Stock, Price Per Share | $ / shares		$ 1.848
Stock Issued Warrents Exercisable		2,536,391
Pre-funded Warrants [Member]
Fair Value Adjustment of Warrants | $	$ 1,631
Pyment Of Issuance Cost Warrants | $	$ 45					$ 84
Proceeds from Common Shares | $						3,047
Stock Issued During Period, Shares, New Issues (in shares)	2,106,853
Stock Issued Warrents Exercisable		2,106,853
Class of Warrant or Right, Exercise Price of Warrants or Rights (in CAD per share) | $ / shares	$ 0.0001	$ 0.0001
Common Stock [Member]
Pyment Of Issuance Cost Warrants | $						78
Proceeds from Common Shares | $						$ 2,822
Class of Warrant or Right, Exercise Price of Warrants or Rights (in CAD per share) | $ / shares	$ 3.003			$ 0.125		$ 0.125	$ 0.125
Common Class A [Member]
Common Stock, Votes Per Share | Vote				1		1	1
Common Stock, Shares, Issued				9,399,404		9,399,404	9,399,404			7,435,533
Common Stock, Shares, Outstanding				9,399,404		9,399,404	9,399,404			7,435,533
Common Class B [Member]
Common Stock, Votes Per Share | Vote				10		10	10
Common Stock, Shares, Issued				0		0	0			0
Common Stock, Shares, Outstanding				0		0	0			0
Common Stock, Dividend Rate, Percentage						5.00%
Common Stock, Redemption Price Per Share (in CAD per share) | $ / shares							$ 4.8
Common Class C [Member]
Common Stock, Shares, Issued				0		0	0			0
Common Stock, Shares, Outstanding				0		0	0			0
Common Stock, Dividend Rate, Percentage						5.00%
Common Stock, Redemption Price Per Share (in CAD per share) | $ / shares							$ 1.2
Common Class D and Common Class E [Member]
Common Stock, Shares, Issued				0		0	0
Common Stock, Shares, Outstanding				0		0	0
Minimum [Member] | Common Class D and Common Class E [Member]
Common Stock, Dividend Rate, Percentage						0.50%
Maximum [Member] | Common Class D and Common Class E [Member]
Common Stock, Dividend Rate, Percentage						2.00%