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RELATED-PARTY TRANSACTIONS (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended			3 Months Ended								6 Months Ended	9 Months Ended	12 Months Ended		84 Months Ended	108 Months Ended
	Jul. 20, 2023	Mar. 31, 2025	Jan. 31, 2025	Oct. 31, 2023	Apr. 30, 2025	Jan. 31, 2025	Oct. 31, 2024	Jul. 31, 2024	Apr. 30, 2024	Jan. 31, 2024	Oct. 31, 2023	Jul. 31, 2023	Oct. 31, 2023	Jan. 31, 2025	Apr. 30, 2025	Apr. 30, 2024	Apr. 30, 2023	Apr. 30, 2025
Related Party Transaction [Line Items]
Stock award to director															$ 62	$ 222
Average price paid per share (in dollars per share)					$ 1.66	$ 1.86	$ 1.31	$ 0.93	$ 0.79	$ 0.73	$ 0.73	$ 0.73					$ 0.42	$ 0.73
Director \| Butler National Corporation 2016 Equity Incentive Plan
Related Party Transaction [Line Items]
Stock award to director (in shares)		39,430	87,000	300,000
Shares issued, price per share (in dollars per share)		$ 1.59	$ 1.73	$ 0.74		$ 1.73					0.74		$ 0.74	$ 1.73
Stock award to director		$ 63	$ 150	$ 222
Director David Hayden \| Consulting Fees
Related Party Transaction [Line Items]
Consulting fees															123	135
Chief Executive Officer
Related Party Transaction [Line Items]
Severance costs	$ 1,800
Stock repurchased during period, shares (in shares)	1,933,402
Average price paid per share (in dollars per share)	$ 0.739
Vice President
Related Party Transaction [Line Items]
Severance costs	$ 2,700
Stock repurchased during period, shares (in shares)	3,956,267
Average price paid per share (in dollars per share)	$ 0.739
Wayne Stewart
Related Party Transaction [Line Items]
Compensation expense, excluding cost of good and service sold															292	315
Jeff Shinkle
Related Party Transaction [Line Items]
Compensation expense, excluding cost of good and service sold															$ 0	$ 162
Related Party \| Director
Related Party Transaction [Line Items]
Employee benefits and share based compensation														$ 90,000
Related Party \| Director \| Butler National Corporation 2016 Equity Incentive Plan
Related Party Transaction [Line Items]
Stock award to director (in shares)													300,000
Shares issued, price per share (in dollars per share)				$ 0.74							$ 0.74		$ 0.74
Stock award to director													$ 222
Related Party \| Executive Chariman
Related Party Transaction [Line Items]
Employee benefits and share based compensation														$ 160,000