Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)	6 Months Ended
	Sep. 30, 2015		Sep. 30, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 3,057,920		$ 1,891,103
Adjustments to reconcile net income to net cash used in operating activities:
Gain on sale of marketable securities	0		(8,410)
Loss (Gain) on sale of property and equipment	5,381		(273,861)
Change in accounts receivable and inventory reserves	(61,616)		(275,203)
Depreciation and amortization	371,121		439,171
Change in cash surrender value of life insurance	(14,575)		(5,246)
Warranty reserve.	(82,995)		(151,600)
Compensation expense related to stock options	0		8,958
Change in operating assets and liabilities:
Accounts receivable	(8,327,227)		(6,508,320)
Notes receivable and other non-trade receivables	111,274		443,227
Inventories	(3,212,440)		3,638,530
Prepaid expenses and other assets	115,057		210,050
Accounts payable	3,017,840		(797,292)
Accrued expenses	(58,762)		34,710
Income taxes receivable/ payable	1,098,013		777,735
Total adjustments	(7,038,927)		(2,467,553)
Net cash used in operating activities	(3,981,007)		(576,450)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of marketable securities	(1,863,621)		(3,973,218)
Proceeds from sale of marketable securities	0		511,571
Proceeds from sale of property and equipment	19,163		823,671
Capital expenditures	(513,433)		(1,553,223)
Net cash used in investing activities	(2,357,891)		(4,191,199)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from line of credit	14,291,273		$ 1,330,888
Payment on line of credit	(17,909,633)
Repurchase of stock options	0		$ (112,935)
Net cash provided by (used in) financing activities	(3,618,360)		1,217,953
NET DECREASE IN CASH AND CASH EQUIVALENTS	(9,957,258)		(3,549,696)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	14,165,120	[1]	3,758,888
CASH AND CASH EQUIVALENTS AT END OF PERIOD	4,207,862		209,192
SUPPLEMENTAL SCHEDULE OF NON-CASH INVESTING ACTIVITIES:
Change in fair value of marketable securities	(866,430)		(138,653)
Finished goods inventory transferred to equipment leased to customers	1,143,635		1,132,115
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:
Interest	45,118		16,280
Income taxes	$ 267,134		$ 804,200

[1] Derived from audited financial statements