Note 2 - Sale of Subsidiaries and Subsequent Events - Summary of Condensed Statements of Operations (Details) - USD ($) shares in Thousands		3 Months Ended			6 Months Ended
		Jul. 31, 2023		Jul. 31, 2022	Jul. 31, 2023		Jul. 31, 2022
Sale of marine technology products		$ 8,750,000	[1]	$ 8,713,000	$ 21,336,000	[1]	$ 17,800,000
Total revenues		8,750,000	[1]	8,713,000	21,336,000	[1],[2],[3],[4]	17,800,000
Total cost of sales		5,483,000	[1]	5,175,000	12,652,000	[1]	10,973,000
Gross profit		3,267,000	[1]	3,538,000	8,684,000	[1]	6,827,000
Selling, general and administrative		3,514,000	[1]	3,789,000	7,388,000	[1]	8,061,000
Research and development		842,000	[1]	833,000	1,615,000	[1]	1,847,000
Depreciation and amortization		459,000	[1]	467,000	940,000	[1]	946,000
Total operating expenses		4,815,000	[1]	5,089,000	9,943,000	[1]	10,854,000
Operating income (loss)		(1,548,000)	[1]	(1,551,000)	(1,259,000)	[1]	(4,027,000)
Other, net		131,000	[1]	(76,000)	20,000	[1]	(194,000)
Total other income (expense)		131,000	[1]	(76,000)	20,000	[1]	(194,000)
Income (loss) from continuing operations before income taxes		(1,417,000)	[1]	(1,627,000)	(1,239,000)	[1]	(4,221,000)
Provision for income taxes		(77,000)	[1]	(131,000)	(495,000)	[1]	(342,000)
Net (loss) income from continuing operations		(1,494,000)	[1]	(1,758,000)	(1,734,000)	[1]	(4,563,000)
Preferred stock dividends - declared		0	[1]	0	0	[1]	(947,000)
Preferred stock dividends - undeclared		(947,000)	[1]	(947,000)	(1,894,000)	[1]	(947,000)
Net loss attributable to common stockholders		$ (2,441,000)	[1]	$ (2,867,000)	$ (3,628,000)	[1]	$ (6,233,000)
Basic (in shares)		13,792	[1]	13,782	13,791	[1]	13,779
Diluted (in shares)		13,792	[1]	13,782	13,791	[1]	13,779
Marine Technology Products [Member]
Sale of marine technology products		$ 8,750,000		$ 8,713,000	$ 21,336,000		$ 17,800,000
Total cost of sales		5,483,000	[1],[5]	$ 5,175,000	12,652,000	[1]	$ 10,973,000
Pro Forma Adjustments [Member]
Sale of marine technology products		0
Total revenues		0			0
Total cost of sales
Gross profit		0			0
Selling, general and administrative		0			0
Research and development		0			0
Depreciation and amortization		0
Total operating expenses		0			0
Operating income (loss)		0			0
Other, net		204,000			407,000
Total other income (expense)		204,000	[6]		407,000
Income (loss) from continuing operations before income taxes		204,000			407,000
Provision for income taxes		0
Net (loss) income from continuing operations		204,000			407,000
Preferred stock dividends - declared
Preferred stock dividends - undeclared					0
Net loss attributable to common stockholders					$ 0
Basic (in shares)
Diluted (in shares)
Pro Forma Adjustments [Member] | Marine Technology Products [Member]
Total cost of sales		0			$ 0
Pro Forma [Member]
Sale of marine technology products		7,560,000	[2],[3],[4]		18,158,000
Total revenues		7,560,000			18,158,000
Total cost of sales		4,619,000			10,680,000
Gross profit		2,941,000			7,478,000
Selling, general and administrative		2,898,000			6,189,000
Research and development		447,000			878,000
Depreciation and amortization		302,000			634,000
Total operating expenses		3,647,000			7,701,000
Operating income (loss)		(706,000)			(223,000)
Other, net		237,000			350,000
Total other income (expense)		237,000			350,000
Income (loss) from continuing operations before income taxes		(469,000)			127,000
Provision for income taxes		(101,000)			(512,000)
Net (loss) income from continuing operations		(570,000)			(385,000)
Preferred stock dividends - declared					0
Preferred stock dividends - undeclared		(947,000)			(1,894,000)
Net loss attributable to common stockholders		$ (1,517,000)			$ (2,279,000)
Basic (in shares)		13,792			13,791
Diluted (in shares)		13,792			13,791
Pro Forma [Member] | Marine Technology Products [Member]
Total cost of sales		$ 4,619,000			$ 10,680,000
Subsidiaries [Member]
Sale of marine technology products	[8]	(1,190,000)	[7]		(3,178,000)
Total revenues	[8]	(1,190,000)			(3,178,000)
Total cost of sales	[8]	(864,000)			(1,972,000)
Gross profit	[8]	(326,000)			(1,206,000)
Selling, general and administrative	[8]	(616,000)			(1,199,000)
Research and development	[8]	(395,000)			(737,000)
Depreciation and amortization	[8]	(157,000)			(306,000)
Total operating expenses	[8]	(1,168,000)			(2,242,000)
Operating income (loss)	[8]	842,000			1,036,000
Other, net	[8]	(98,000)			(77,000)
Total other income (expense)	[8]	(98,000)			(77,000)
Income (loss) from continuing operations before income taxes	[8]	744,000			959,000
Provision for income taxes	[8]	(24,000)			(17,000)
Net (loss) income from continuing operations	[8]	720,000			942,000
Preferred stock dividends - declared	[8]
Preferred stock dividends - undeclared	[8]				0
Net loss attributable to common stockholders	[8]				$ 0
Basic (in shares)	[8]
Diluted (in shares)	[8]
Subsidiaries [Member] | Marine Technology Products [Member]
Total cost of sales	[8]	$ (864,000)			$ (1,972,000)	[5]

[1] Reflects the condensed consolidated balance sheet as of July 31, 2023 and condensed consolidated statement of operations for the three and six months ended July 31, 2023 and 2023 in the Form 10-Q.

[2] Adjustments represent the disposition of assets and liabilities of the Klein operations.

[3] To record the net cash proceeds from the Sale of Klein paid on the Closing Date of $11.5 million, less estimated closing costs, estimated pay-off of the Note Payable, and estimated transaction costs, primarily legal expenses and investment broker fees, associated with the sale, all of which were incurred as part of the consummation of the Sale of Klein.

[4] To record the pay-off of the Note Payable, net of prepaid interest and debt acquisition costs, due to Sachem Capital.

[5] Adjustments to accumulated deficit reflect the estimated gain on Sale of Klein. The estimated gain has not been reflected in the accompanying statements of operations as it is not related to continuing operations. The actual gain or loss on Sale of Klein will be recorded in the Company's financial statements for the quarter ending October 31, 2023, and will differ from this estimate.

[6] Reflects removal of interest expense that would not have been incurred if the Sale of Klein had been completed February 1, 2021.

[7] Adjustments represent the elimination of income and expenses of the Klein operations.

[8] Reflects the consummation of the Sale of Klein in accordance with the terms of the SPA.