Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Jan. 31, 2019	Apr. 30, 2018
CURRENT ASSETS:
Cash	$ 8,803	$ 7,353
Accounts receivable	3,775	3,107
Income tax receivable, net		219
Inventories
Parts and raw materials	6,766	5,858
Work in process	1,824	1,234
Finished goods	73	27
Total inventory net of allowances	8,663	7,119
Prepaid expenses and other current assets	1,407	978
Total current assets	22,648	18,776
PROPERTY, PLANT AND EQUIPMENT:
Land and building	6,917	5,232
Aircraft	6,157	6,157
Machinery and equipment	4,001	3,922
Office furniture and fixtures	7,365	6,658
Leasehold improvements	4,032	4,032
	28,472	26,001
Accumulated depreciation	(16,485)	(15,725)
Total property, plant and equipment	11,987	10,276
SUPPLEMENTAL TYPE CERTIFICATES (net of accumulated amortization of $5,808 at January 31, 2019 and $5,164 at April 30, 2018)	6,510	6,597
OTHER ASSETS:
Deferred tax asset	193	193
Other assets (net of accumulated amortization of $9,136 at January 31, 2019 and $8,213 at April 30, 2018)	4,788	5,589
Total other assets	4,981	5,782
Total assets	46,126	41,431
CURRENT LIABILITIES:
Promissory notes		2,387
Current maturities of long-term debt	1,441	1,612
Less current maturities of capital lease obligation	8
Accounts payable	1,695	2,215
Customer deposits	3,260	1,396
Gaming facility mandated payment	975	1,219
Compensation and compensated absences	1,695	1,439
Income taxes payable	996
Other current liabilities	310	162
Total current liabilities	10,380	10,430
Long-term debt, net of current maturities	686	1,735
Long-term capital lease obligation	1,691
Total long-term liabilities	2,377	1,735
Total liabilities	12,757	12,165
STOCKHOLDERS' EQUITY:
Common stock, par value $.01: authorized 100,000,000 shares issued 66,196,854 and outstanding 64,050,508 shares at January 31, 2019 and issued 66,196,854 and outstanding 64,743,317 shares at April 30, 2018	662	662
Capital contributed in excess of par	14,231	14,231
Treasury stock at cost, 2,146,346 shares at January 31, 2019 and 1,453,537 shares at April 30, 2018	(1,165)	(951)
Retained earnings	13,630	10,060
Total stockholders' equity Butler National Corporation	27,358	24,002
Noncontrolling interest in BHCMC, LLC	6,011	5,264
Total stockholders' equity	33,369	29,266
Total liabilities and stockholders' equity	46,126	41,431
Preferred Class A [Member]
STOCKHOLDERS' EQUITY:
Preferred stock
Preferred Class B [Member]
STOCKHOLDERS' EQUITY:
Preferred stock