Consolidated Statements of Cash Flows (Unaudited) (USD $)	6 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities
Net income (loss)	$ 937,000us-gaap_NetIncomeLoss	$ (587,000)us-gaap_NetIncomeLoss
Adjustments to reconcile net income (loss) to net cash provided by operations
Depreciation and amortization	2,727,000us-gaap_DepreciationAndAmortization	2,749,000us-gaap_DepreciationAndAmortization
Gains on sales of marketable securities	(4,000)us-gaap_GainLossOnInvestments
Deferred income taxes	(862,000)	(375,000)
Discounts earned on bonds	(2,000)	(2,000)
(Increase) decrease in current assets (net of acquisitions)
Accounts receivable, net	2,003,000	(25,000)
Inventories	13,000us-gaap_IncreaseDecreaseInInventories	18,000us-gaap_IncreaseDecreaseInInventories
Prepaid expenses and other assets	139,000	427,000
Income tax receivable	1,183,000	289,000
Increase (decrease) in liabilities (net of acquisitions)
Accounts payable	23,000	(66,000)
Accrued liabilities	(31,000)	(1,874,000)
Income taxes	(123,000)	79,000
Net cash provided by operating activities	3,764,000	145,000
Cash flows from investing activities
Sales of marketable securities	4,044,000
Purchases of marketable securities	(10,977,000)
Purchases of property, plant and equipment	(386,000)	(209,000)
Net cash used in investing activities	(7,319,000)	(209,000)
Decrease in cash and cash equivalents	(3,555,000)	(64,000)
Cash and cash equivalents
Beginning of period	15,410,000	11,338,000
End of period	11,855,000	11,274,000
Interest paid during period	112,000us-gaap_InterestPaid	110,000us-gaap_InterestPaid
Net income taxes (refunded) paid during period	(899,000)us-gaap_IncomeTaxesPaidNet	17,000us-gaap_IncomeTaxesPaidNet
Subscription Arrangement [Member]
Increase (decrease) in liabilities (net of acquisitions)
Deferred subscriptions	11,000	17,000
Deferred Maintenance Agreement [Member]
Increase (decrease) in liabilities (net of acquisitions)
Deferred subscriptions	(1,578,000)	(1,390,000)
Deferred Installation Contracts [Member]
Increase (decrease) in liabilities (net of acquisitions)
Deferred subscriptions	$ (672,000)	$ 885,000

The sum of the periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings. This is called accretion if the security was purchased at a discount and amortization if it was purchased at premium. As a noncash item, this element is an adjustment to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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