Condensed Consolidated Statements Of Cash Flows (USD $)	6 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Cash flows from operations:
Net income	$ 3,641,000	$ 3,555,000
Adjustments to reconcile net income to cash provided by operating activities:
Purchases of marketable securities (including money funds)	(22,965,000)	(45,195,000)
Proceeds from sale and maturity of marketable securities	23,339,000	42,706,000
Change in fair value of marketable securities	(4,835,000)	(1,797,000)
Deferred income taxes	1,699,000	(2,364,000)
Depreciation and amortization	514,000	407,000
Provision for doubtful accounts	240,000	100,000
Stock-based compensation	92,000
Change in assets and liabilities:
Accounts receivable	(202,000)	291,000
Costs and estimated earnings in excess of billings	4,071,000	(2,139,000)
Inventories	(1,779,000)	488,000
Prepaid expenses	367,000	544,000
Account payable	791,000	2,009,000
Customer deposits	7,380,000	4,442,000
Accrued expenses and other	164,000	818,000
Total adjustments	8,876,000	310,000
Cash flows provided by operating activities	12,517,000	3,865,000
Cash flows used in investing activities:
Capital expenditures	(730,000)	(851,000)
Cash flows used in investing activities	(730,000)	(851,000)
Net increase in cash	11,787,000	3,014,000
Cash at:
Beginning of period	1,715,000	3,004,000
End of period	$ 13,502,000	$ 6,018,000

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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).