Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operations:
Net income (loss)	$ 1,575,000	$ (1,096,000)
Adjustments to reconcile net income (loss) to cash used in operating activities:
Purchases of marketable securities	(51,115,000)	(134,896,000)
Proceeds from sale and maturity of marketable securities	50,619,000	134,567,000
Change in fair value of marketable securities	(482,000)	433,000
Deferred income taxes	299,000	(244,000)
Depreciation and amortization	362,000	325,000
Provision for doubtful accounts	5,000
Stock-based compensation	5,000	63,000
Changes in assets and liabilities:
Accounts receivable	(150,000)	718,000
Costs and estimated earnings in excess of billings	(1,648,000)	(2,014,000)
Inventories	(2,301,000)	434,000
Prepaid expenses & other current assets	(125,000)	(670,000)
Accounts payable	339,000	(170,000)
Customer deposits	1,717,000	1,198,000
Accrued expenses	135,000	(212,000)
Total adjustments	(2,340,000)	(468,000)
Cash flows used in operating activities	(765,000)	(1,564,000)
Cash flows used in investing activities:
Capital expenditures	(29,000)
Cash flows used in investing activities	(29,000)
Net decrease in cash and cash equivalents	(794,000)	(1,564,000)
Cash and cash equivalents at:
Beginning of period	11,152,000	7,193,000
End of period	$ 10,358,000	$ 5,629,000