Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands		Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Parent [Member]	Noncontrolling Interest [Member]	Total
Balance (in shares) at Apr. 30, 2020		77,719,677		3,321,415
Balance at Apr. 30, 2020		$ 777	$ 15,600	$ (1,713)	$ 18,147	$ 32,811	$ 4,993	$ 37,804
Stock repurchase (in shares)				212,000
Stock repurchase				$ (108)		(108)		(108)
Deferred compensation, restricted stock			150			150		150
Net income (loss)					(15)	(15)	(439)	(454)
Deferred compensation, restricted stock			(150)			(150)		(150)
Balance (in shares) at Jul. 31, 2020		77,719,677		3,533,415
Balance at Jul. 31, 2020		$ 777	15,750	$ (1,821)	18,132	32,838	4,554	37,392
Balance (in shares) at Apr. 30, 2020		77,719,677		3,321,415
Balance at Apr. 30, 2020		$ 777	15,600	$ (1,713)	18,147	32,811	4,993	37,804
Net income (loss)								980
Balance (in shares) at Jan. 31, 2021		77,719,677		3,686,330
Balance at Jan. 31, 2021		$ 777	16,049	$ (1,898)	18,956	33,884	5,164	39,048
Balance (in shares) at Jul. 31, 2020		77,719,677		3,533,415
Balance at Jul. 31, 2020		$ 777	15,750	$ (1,821)	18,132	32,838	4,554	37,392
Stock repurchase (in shares)				152,915
Stock repurchase				$ (77)		(77)		(77)
Deferred compensation, restricted stock			150			150		150
Net income (loss)					321	321	181	502
Deferred compensation, restricted stock			(150)			(150)		(150)
Balance (in shares) at Oct. 31, 2020		77,719,677		3,686,330
Balance at Oct. 31, 2020		$ 777	15,900	$ (1,898)	18,453	33,232	4,735	$ 37,967
Stock repurchase (in shares)	[1]							0
Deferred compensation, restricted stock		0	(149)	0	0	(149)	0	$ (149)
Net income (loss)		0	0	0	503	503	429	932
Deferred compensation, restricted stock		$ 0	149	$ 0	0	149	0	149
Balance (in shares) at Jan. 31, 2021		77,719,677		3,686,330
Balance at Jan. 31, 2021		$ 777	16,049	$ (1,898)	18,956	33,884	5,164	$ 39,048
Stock repurchase (in shares)	[1]							17,303
Balance (in shares) at Apr. 30, 2021		79,070,382		3,703,633
Balance at Apr. 30, 2021		$ 790	16,900	$ (1,909)	19,580	35,361	6,018	$ 41,379
Stock repurchase (in shares)	[1]							0
Deferred compensation, restricted stock			148					$ 148
Net income (loss)					2,906	2,906	1,872	4,778
Deferred compensation, restricted stock			(148)					(148)
Balance (in shares) at Jul. 31, 2021		79,070,382		3,703,633
Balance at Jul. 31, 2021		$ 790	17,048	$ (1,909)	22,486	38,415	7,890	46,305
Balance (in shares) at Apr. 30, 2021		79,070,382		3,703,633
Balance at Apr. 30, 2021		$ 790	16,900	$ (1,909)	19,580	35,361	6,018	41,379
Net income (loss)								10,612
Purchase of noncontrolling interest								6,350
Balance (in shares) at Jan. 31, 2022		79,020,382		3,709,923
Balance at Jan. 31, 2022		$ 790	11,218	$ (1,913)	28,320	38,415	0	38,415
Balance (in shares) at Jul. 31, 2021		79,070,382		3,703,633
Balance at Jul. 31, 2021		$ 790	17,048	$ (1,909)	22,486	38,415	7,890	$ 46,305
Stock repurchase (in shares)				6,290				6,290	[1]
Stock repurchase				$ (4)		(4)		$ (4)
Deferred compensation, restricted stock			149			149		149
Net income (loss)					3,150	3,150		3,150
Deferred compensation, restricted stock			(149)			(149)		(149)
Purchase of noncontrolling interest			(6,119)			(6,119)
Purchase of noncontrolling interest in BHCMC, LLC							(7,890)	(14,009)
Balance (in shares) at Oct. 31, 2021		79,070,382		3,709,923
Balance at Oct. 31, 2021		$ 790	11,078	$ (1,913)	25,636	35,591		$ 35,591
Stock repurchase (in shares)	[1]							0
Deferred compensation, restricted stock		0	(140)	0	0	(140)	0	$ (140)
Net income (loss)		0	0	0	2,684	2,684	0	2,684
Deferred compensation, restricted stock		$ 0	140	$ 0	0	140	0	140
Deferred compensation, restricted stock (in shares)		(50,000)		0
Balance (in shares) at Jan. 31, 2022		79,020,382		3,709,923
Balance at Jan. 31, 2022		$ 790	$ 11,218	$ (1,913)	$ 28,320	$ 38,415	$ 0	$ 38,415

[1] These shares of common stock were purchased through a private transaction