CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $) In Thousands, unless otherwise specified	Common Stock [Member]	Common Stock owed but Not issued [Member]	Capital Contributed in Excess of Par [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Total Stockholders' Equity Butler National Corporation [Member]	Noncontrolling Interest in BHCMC, LLC [Member]	Total
BALANCE at Apr. 30, 2011	$ 572	$ 3	$ 11,911	$ (732)	$ 6,271	$ 18,025	$ 0	$ 18,025
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock options issued to employees and directors	0	0	384	0	0	384	0	384
Contributed capital	0	0	0	0	0	0	1	1
Issuance of stock benefit plan	7	0	271	0	0	278	0	278
Net income	0	0	0	0	1,899	1,899	2,016	3,916
BALANCE at Apr. 30, 2012	579	3	12,567	(732)	8,170	20,587	2,017	22,604
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock for services and other	2	(3)	91	0	0	90	0	90
Stock options issued to employees and directors	0	0	110	0	0	110	0	110
BHCMC distribution noncontrolling member	0	0	0	0	0	0	(320)	(320)
Issuance of stock benefit plan	15	0	266	0	0	281	0	281
Net income	0	0	0	0	(148)	(148)	957	809
BALANCE at Apr. 30, 2013	596	0	13,034	(732)	8,022	20,920	2,654	23,574
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock for services and other
Stock options issued to employees and directors	0	0	22	0	0	22	0	22
Issuance of stock benefit plan	18	0	226	0	0	244	0	244
Net income	0	0	0	0	112	112	402	514
BALANCE at Apr. 30, 2014	$ 614	$ 0	$ 13,282	$ (732)	$ 8,134	$ 21,298	$ 3,056	$ 24,354