Condensed Consolidated Balance Sheets - USD ($)	Jun. 30, 2020	Sep. 30, 2019
Current Assets:
Cash and cash equivalents	$ 18,564,000	$ 10,302,000
Marketable securities at fair value (cost $105,388,000 at June 30, 2020 and $104,176,000 at September 30, 2019)	105,675,000	105,322,000
Accounts receivable, less allowance for doubtful accounts of $419,000 at June 30, 2020 and $459,000 at September 30, 2019	1,609,000	1,603,000
Costs and estimated earnings in excess of billings	10,064,000	13,838,000
Inventories, net	24,562,000	25,366,000
Prepaid expenses and other current assets	1,649,000	499,000
Total current assets	162,123,000	156,930,000
Property and equipment, net	8,391,000	8,389,000
Other assets	53,000	53,000
Total Assets	170,567,000	165,372,000
Current liabilities:
Accounts payable	2,089,000	1,907,000
Customer deposits	2,651,000	1,918,000
Accrued expenses and other current liabilities	2,694,000	2,660,000
Total current liabilities	7,434,000	6,485,000
Deferred and other income taxes	1,306,000	3,372,000
Total liabilities	8,740,000	9,857,000
Commitments and contingencies
Shareholders' equity:
Preferred stock, par value $.10 per share; 300,000 shares authorized; none issued	0	0
Capital in excess of par value	12,313,000	12,159,000
Retained earnings	148,053,000	141,897,000
Total shareholders' equity	161,827,000	155,515,000
Total Liabilities and Shareholders' Equity	170,567,000	165,372,000
Common Stock [Member]
Shareholders' equity:
Common stock	1,229,000	1,228,000
Total shareholders' equity	1,229,000	1,228,000
Class B Stock [Member]
Shareholders' equity:
Common stock	232,000	231,000
Total shareholders' equity	$ 232,000	$ 231,000