Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2019	Jan. 31, 2018
REVENUE:
Revenues	$ 14,292	$ 11,010	$ 42,993	$ 33,816
COSTS AND EXPENSES:
Marketing and advertising	1,021	920	3,056	2,729
Employee benefits	532	480	1,518	1,416
Depreciation and amortization	415	362	1,198	1,344
General, administrative and other	1,873	1,426	5,852	4,112
Total costs and expenses	12,479	10,571	38,461	32,414
OPERATING INCOME	1,813	439	4,532	1,402
OTHER INCOME (EXPENSE):
Interest expense	(44)	(83)	(169)	(250)
Other income, net		1		1
Refund of sales/use tax	385		1,995
Total other income (expense)	341	(82)	1,826	(249)
INCOME BEFORE INCOME TAXES	2,154	357	6,358	1,153
INCOME TAXES:
Provision for income taxes	495	10	1,320	191
NET INCOME	1,659	347	5,038	962
Net income attributable to noncontrolling interest in BHCMC, LLC	(319)	(327)	(1,468)	(620)
NET INCOME ATTRIBUTABLE TO BUTLER NATIONAL CORPORATION	$ 1,340	$ 20	$ 3,570	$ 342
BASIC EARNINGS PER COMMON SHARE (in dollars per share)	$ 0.02	$ 0	$ 0.06	$ 0.01
WEIGHTED AVERAGE SHARES USED IN PER SHARE CALCULATION (in shares)	63,976,255	64,506,986	64,356,380	64,531,138
DILUTED EARNINGS PER COMMON SHARE (in dollars per share)	$ 0.02	$ 0	$ 0.06	$ 0.01
WEIGHTED AVERAGE SHARES USED IN PER SHARE CALCULATION (in shares)	63,976,255	64,506,986	64,356,380	64,531,138
Professional Services [Member]
REVENUE:
Revenues	$ 7,617	$ 7,559	$ 23,423	$ 22,340
COSTS AND EXPENSES:
Cost of services and products	4,996	4,747	14,735	14,344
Aerospace Products [Member]
REVENUE:
Revenues	6,675	3,451	19,570	11,476
COSTS AND EXPENSES:
Cost of services and products	$ 3,642	$ 2,636	$ 12,102	$ 8,469