Condensed Consolidated Statements Of Cash Flows (USD $)	3 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Cash flows from operations:
Net income	$ 875,000	$ 1,105,000
Adjustments to reconcile net income to cash provided (used) by operating activities:
Purchases of marketable securities	(5,898,000)	(5,047,000)
Proceeds from sale and maturity of marketable securities	6,695,000	4,768,000
Change in fair value of marketable securities	(2,093,000)	(2,868,000)
Deferred income taxes	325,000	860,000
Depreciation and amortization	261,000	191,000
Provision for doubtful accounts	90,000	90,000
Stock-based compensation	46,000
Change in assets and liabilities:
Accounts receivable	237,000	403,000
Costs and estimated earnings in excess of billings	2,374,000	(1,899,000)
Inventories	(2,646,000)	(681,000)
Prepaid expenses	131,000	37,000
Account payable	275,000	712,000
Customer deposits	2,364,000	1,419,000
Accrued expenses and other	(438,000)	(90,000)
Total adjustments	1,723,000	(2,105,000)
Cash flows provided (used) by operating activities	2,598,000	(1,000,000)
Cash flows used in investing activities:
Capital expenditures	(21,000)	(135,000)
Cash flows used in investing activities	(21,000)	(135,000)
Net increase (decrease) in cash and cash equivalents	2,577,000	(1,135,000)
Cash and cash equivalents at:
Beginning of period	1,715,000	3,004,000
End of period	$ 4,292,000	$ 1,869,000

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).