Consolidated Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended				9 Months Ended		12 Months Ended
	Sep. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
OPERATING ACTIVITIES:
Net (loss) income	$ 2,196,000	$ 430,000	$ (222,000)	$ 1,256,000	$ 3,522,000	$ 2,909,000
us-gaap_AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract
Depreciation and amortization					2,776,000	5,011,000
Stock-based compensation expense					859,000	150,000
Deferred income taxes					(260,000)	69,000
Non-cash investment loss (income)					0	1,000,000
Equity in loss of affiliate company					528,000	701,000
Changes in operating assets and liabilities:
Accounts receivable, net					216,000	7,345,000
Other current assets					(1,717,000)	(2,329,000)
Other long-term assets					17,000	563,000
Accounts payable					388,000	(78,000)
Accrued payroll					287,000	53,000
Deferred revenue, current portion					(1,046,000)	2,649,000
Accrued expenses					79,000	281,000
Other current liabilities					(506,000)	40,000
Deferred revenue, net of current portion					(104,000)	(112,000)
Net cash provided by operating activities					5,039,000	18,252,000
INVESTING ACTIVITIES:
Purchases of property and equipment					(3,733,000)	(4,845,000)
Advances on notes and interest receivable		(200,000)			(200,000)	(450,000)	$ (650,000)
Proceeds from payments on notes receivable					152,000	147,000
Purchase of marketable securities					1,831,000	1,776,000
Maturities of marketable securities					1,728,000	1,602,000
Purchase of long-term investment					(98,000)	(155,000)
Net cash used for investing activities					(3,982,000)	(5,477,000)
FINANCING ACTIVITIES:
Repurchases of common stock					5,412,000	1,528,000
Net cash used for financing activities					(5,412,000)	(1,528,000)
Effects of exchange rate changes on cash					(65,000)	(32,000)
Net increase (decrease) in cash					(4,420,000)	11,215,000
Cash at beginning of period		$ 26,918,000		$ 20,399,000	26,918,000	20,399,000	20,399,000
Cash at end of period	$ 22,498,000		$ 31,614,000		22,498,000	31,614,000	$ 26,918,000
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:
Cash paid during the period for income taxes					1,070,000	168,000
Purchases of property and equipment, accrued but not paid					$ 144,000	$ 0