Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jan. 31, 2013	Apr. 30, 2012
Current assets:
Cash and cash equivalents	$ 5,222	$ 4,782
Marketable securities	16,409	17,658
Accounts receivable, net of allowance for doubtful accounts of $355 at January 31, 2013 and $400 at April 30, 2012	8,357	10,866
Costs and estimated earnings in excess of billings, net	8,617	7,207
Inventories	37,756	34,299
Deferred income taxes	2,850	3,152
Prepaid expenses and other	1,507	1,398
Total current assets	80,718	79,362
Property, plant and equipment, at cost ,less accumulated depreciation and amortization	8,391	8,374
Deferred income taxes	6,023	5,692
Goodwill and other intangible assets	804	873
Cash surrender value of life insurance and cash held in trust	10,605	10,133
Investment in affiliates	806	809
Other assets	933	984
Total assets	108,280	106,227
Current liabilities:
Short-term credit obligations	5,178	6,383
Accounts payable - trade	1,368	2,644
Accrued liabilities	8,155	6,986
Income taxes payable		96
Total current liabilities	14,701	16,109
Capital lease obligation- noncurrent		15
Deferred compensation	10,314	10,179
Deferred rent and other liabilities	819	792
Total liabilities	25,834	27,095
Commitments and contingencies
Stockholders' equity:
Preferred stock -$1.00 par value
Common stock-$1.00 par value, issued 9,163,940 shares	9,164	9,164
Additional paid-in capital	51,526	50,797
Retained earnings	20,705	18,660
Common stock reacquired and held in treasury - at cost (732,554 shares at January 31, 2013 and 800,787 shares at April 30, 2012)	(3,344)	(3,659)
Accumulated other comprehensive income	4,395	4,170
Total stockholders' equity	82,446	79,132
Total liabilities and stockholders' equity	$ 108,280	$ 106,227