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Equity (Details Textual) - USD ($) $ / shares in Units, $ in Thousands									1 Months Ended			3 Months Ended						9 Months Ended		12 Months Ended
	Nov. 01, 2023	Jun. 16, 2023	Jun. 13, 2023	May 31, 2023	May 16, 2023	Mar. 08, 2021	Jun. 12, 2018	Jun. 08, 2018	Feb. 28, 2023	Nov. 30, 2022	May 31, 2022	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022	May 03, 2022	Feb. 28, 2022	Feb. 07, 2022	Mar. 11, 2013
Equity
Dividends on preferred stock													$ 176	$ 157	$ 454	$ 624	$ 370
Dividends on common stock												$ 0.075			$ 0.075			$ 0.225	$ 0.225
Treasury Stock, Common, Shares												2,944,000						2,944,000		2,705,000
Amount of warrants aggregate exercise price																		$ 5,000
Unrecognized compensation cost												$ 1,700						$ 1,700
Weighted-average period																		1 year
Deferred stock units granted																						290,000
Cash dividend paid												$ 0.075	$ 0.075	$ 0.075	$ 0.075	$ 0.075	$ 0.075
Redemption of preferred stock													$ 7,359	$ 1,000	$ 1,000	$ 2,000
Board of Directors [Member]
Equity
Preferred Stock, Liquidation Preference, Value																							$ 1,000
Preferred stock, liquidation preference per share																							$ 8.5
Employee [Member] | Lumo Finland Grant [Member]
Equity
Percentage of ownership										5.10%
Employee [Member] | Lumo Sweden [Member]
Equity
Percentage of ownership										2.30%
Dividend Paid [Member]
Equity
Preferred stock dividend rate																				$ 0.5301
Dividends on preferred stock																				$ 500
Preferred Stock [Member]
Equity
Redemption of preferred stock, shares													866,000	117,000	117,000	235,000
Redemption of preferred stock													$ 7,359	$ 1,000	$ 1,000	$ 2,000
Preferred Stock [Member] | Stock Repurchase Program [Member]
Equity
Redemption of preferred stock, shares																		235,294
Redemption of preferred stock																		$ 2,000
Common Stock
Equity
Number of common stock shares issued											72,657
Warrant [Member]
Equity
Stock Repurchased and Retired During Period, Shares											136,987
Class B common stock [Member]
Equity
Number of stock authorized to be repurchased																								7,000,000
Number of shares repurchased, shares												0			0			0
Remaining number of shares available for repurchase												4,700,000						4,700,000
Treasury Stock, Common, Shares												2,900,000						2,900,000		2,700,000
Treasury stock cost																		$ 22,500		$ 19,000
Weighted average cost per share																		$ 7.63		$ 7.03
Warrants to purchase shares												0						0
Restricted Stock, Shares Issued Net of Shares for Tax Withholdings									290,000	123,302						290,000
Description of vested period										May 2023 and up to May 2025
Class B common stock [Member] | 2021 Plan
Equity
Maximum number of shares reserved for the grant of awards						1,000,000
Class B common stock [Member] | Stock Repurchase Program [Member]
Equity
Number of shares repurchased, shares																			639,393
Aggregate amount of shares repurchased																			$ 4,400
Class B common stock [Member] | Stock-Based Compensation [Member] | 2021 Plan
Equity
Stock option and incentive plan to reserve						500,000
Class B common stock [Member] | Howard S. Jonas [Member]
Equity
Warrants to purchase shares								1,048,218
Amount of warrants aggregate exercise price								$ 5,000
Warrants exercise price per share								$ 4.77
Shares repurchased for withholding tax obligations in connection to the exercise of the options				158,109
Exercise of stock options, shares				256,818
Stock issued during period, shares, issued for cashless exercise				98,709
Class B common stock [Member] | Investor [Member]
Equity
Amount of aggregate sales price							$ 1,000
Warrants to purchase shares							209,644
Amount of warrants aggregate exercise price							$ 1,000
Warrants exercise price per share							$ 4.77
Class B common stock [Member] | Preferred Stock [Member] | Stock Repurchase Program [Member]
Equity
Redemption of preferred stock, shares			235,294
Redemption of preferred stock, authorized amount																					$ 2,000
Redemption of preferred stock			$ 2,000
Class B common stock [Member] | Common Stock
Equity
Stockholders grant of options purchase													300,000	33,000	290,000		9,000
Exercise of stock options, shares													257,000
Class B common stock [Member] | Warrant [Member]
Equity
Warrants to purchase shares								1,048,218
Exercise of stock options, shares											209,644
Stock issued, value, warrants exercised								$ 5,000
Series 2012-A Preferred Stock [Member] | Preferred Stock [Member] | Stock Repurchase Program [Member]
Equity
Preferred stock dividend rate		$ 0.1349
Redemption of preferred stock, shares		748,064
Redemption Date					Jun. 16, 2023
Price per share					$ 8.5
Preferred stock, shares outstanding		0
Preferred stock dividend redeemable		$ 100
Redemption of preferred stock		$ 6,500
Class A Common Stock and Class B Common Stock [Member] | Subsequent Event [Member]
Equity
Dividends on common stock	$ 0.075
Paid date of declared dividend	Nov. 21, 2023
Record date of declared dividend	Nov. 13, 2023

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