Note 11 - Earnings Per Share ("EPS") - Reconciliation of Basic to Diluted Weighted Average Shares Outstanding (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended																12 Months Ended
		Dec. 31, 2024		Sep. 30, 2024		Jun. 30, 2024		Mar. 31, 2024		Dec. 31, 2023		Sep. 30, 2023		Jun. 30, 2023		Mar. 31, 2023		Dec. 31, 2024		Dec. 31, 2023
Income from continuing operations		$ 228		$ 90		$ 161		$ 43		$ 160	[1]	$ 130	[1]	$ (130)	[1]	$ 185	[1]	$ 522		$ 345
Less: Net income from continuing operations attributable to non-controlling interests																		90		48
Income attributable to LGL Group common stockholders from continuing operations																		432		297
(Loss) income from discontinued operations, net of tax																		0		(28)
Net income attributable to LGL Group common stockholders																		$ 432		$ 269
Weighted average common shares outstanding - basic (in shares)		5,352,937		5,352,937		5,352,937		5,352,937		5,352,937		5,352,937		5,352,937		5,352,937		5,352,937		5,352,937
Warrants (in shares)	[2]																	192,310		0
Restricted stock (in shares)	[2]																	8,576		0
Weighted average common shares outstanding - diluted (in shares)		5,577,062		5,531,969		5,482,543		5,604,430		5,381,685		5,355,006		5,352,937		5,352,937		5,553,823	[2]	5,352,937	[2]
Income from continuing operations (in dollars per share)		$ 0.04	[1]	$ 0.01	[1]	$ 0.03	[1]	$ 0	[1]	$ 0.03	[1]	$ 0.02	[1]	$ (0.02)	[1]	$ 0.03	[1]	$ 0.08		$ 0.06
(Loss) income from discontinued operations (in dollars per share)		0	[1]	0	[1]	0	[1]	0	[1]	0	[1]	0	[1]	0	[1]	(0.01)	[1]	0		(0.01)
Net income attributable to LGL Group common stockholders (in dollars per share)		0.04	[1]	0.01	[1]	0.03	[1]	0	[1]	0.03	[1]	0.02	[1]	(0.02)	[1]	0.03	[1]	0.08		0.05
Income from continuing operations (in dollars per share)		0.04	[1]	0.01	[1]	0.02	[1]	0	[1]	0.02	[1]	0.02	[1]	(0.02)	[1]	0.03	[1]	0.08		0.06
(Loss) income from discontinued operations (in dollars per share)		0	[1]	0	[1]	0	[1]	0	[1]	0	[1]	0	[1]	0	[1]	(0.01)	[1]	0		(0.01)
Net income attributable to LGL Group common stockholders (in dollars per share)		$ 0.04	[1]	$ 0.01	[1]	$ 0.02	[1]	$ 0	[1]	$ 0.02	[1]	$ 0.02	[1]	$ (0.02)	[1]	$ 0.03	[1]	$ 0.08		$ 0.05

[1] Basic and diluted earnings per share are calculated using actual, unrounded amounts. Therefore, (i) the components of earnings per share may not sum to its corresponding total or (ii) the quarterly earnings per share may not sum to the earnings per share on the Consolidated Statements of Operations.

[2] For the year ended December 31, 2023, weighted average shares used for calculating earnings per share excludes warrants to purchase 1,051,664 shares of common stock as well as 20,117 shares from restricted stock awards as the inclusion of these instruments would be antidilutive to the earnings per share calculation. For more information on the warrants and restricted stock, refer to Note 10 - Stockholders' Equity and Note 9 - Stock-Based Compensation, respectively, to these Consolidated Financial Statements.