Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $)	9 Months Ended
	Jan. 31, 2013	Jan. 31, 2012
Cash Flows from Operating Activities:
Net income	$ 968,000	$ 754,000
Adjustments to reconcile net income to net cash provided by operating activities:
Share-based compensation expense	89,000	69,000
Depreciation	258,000	272,000
Amortization	154,000	166,000
Provision for doubtful accounts	23,000	27,000
Loss on disposal of equipment		6,000
Deferred income taxes	93,000	(108,000)
Changes in operating assets and liabilities:
Accounts receivable	(798,000)	128,000
Inventories	167,000	(387,000)
Income tax payable/receivable	120,000	(21,000)
Accounts payable	310,000	9,000
Accrued expenses	(225,000)	(176,000)
Other	(90,000)	(21,000)
Net cash provided by operating activities	1,069,000	718,000
Cash Flows from Investing Activities:
Purchases of property and equipment	(214,000)	(260,000)
Net cash (used in) investing activities	(214,000)	(260,000)
Cash Flows from Financing Activities:
Principal payments on note payable to bank	(750,000)	(750,000)
Purchases of common stock for repurchase program	(140,000)
Proceeds from the exercise of stock options	59,000
Principal payments on long-term debt	(136,000)	(113,000)
Net cash (used in) financing activities	(967,000)	(863,000)
Net (decrease) in cash and cash equivalents	(112,000)	(405,000)
Cash and cash equivalents at beginning of period	136,000	460,000
Cash and cash equivalents at end of period	24,000	55,000
Supplemental Disclosure of Cash Flow Information:
Cash paid during the period for interest	53,000	138,000
Cash paid during the period for income taxes	$ 382,000	$ 577,000