Note 16 - Restatement (Unaudited) - Schedule of Restated Income Statements (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Jun. 30, 2024	Sep. 30, 2024	Dec. 31, 2024	Dec. 31, 2023
Net revenues					$ 196,814	$ 262,747
Related Party - Cost of revenues					0	5,197
Cost of revenues					158,357	202,070
Gross profit					38,457	55,480
Selling, general and administrative expense					37,265	43,673
(Gain) Loss on disposal of business			$ (4,558)	$ (3,598)	(1,348)	408
Depreciation and amortization					1,616	2,001
Operating income (loss)					924	9,398
Interest expense					(2,222)	(1,919)
Other (income), net					(171)	(346)
Income (loss) before income tax expense					(1,469)	7,133
Income tax expense					1,218	2,357
Net income (loss)			3,737	3,468	(2,687)	4,776
Net (income) attributable to non-controlling interest					463	874
Net income (loss) attributable to SPAR Group, Inc.					$ (3,150)	$ 3,902
Basic earnings (loss) per common share attributable to SPAR Group, Inc. (in dollars per share)					$ (0.13)	$ 0.17
Diluted earnings (loss) per common share attributable to SPAR Group, Inc. (in dollars per share)					$ (0.13)	$ 0.16
Weighted average common shares – basic (in shares)					23,555	23,333
Weighted average common shares – diluted (in shares)					23,729	24,455
Foreign currency translation adjustments					$ (1,553)	$ 1,283
Comprehensive (income) attributable to non-controlling interest					172	317
Comprehensive income (loss) attributable to SPAR Group, Inc.					$ (4,412)	$ 5,742
Restated Amounts [Member]
Net revenues	$ 37,788		125,984
Related Party - Cost of revenues	0		0
Cost of revenues	29,346		102,448
Gross profit	8,442		23,536
Selling, general and administrative expense	8,558		19,158
(Gain) Loss on disposal of business	960		(4,558)
Depreciation and amortization	454		989
Operating income (loss)	(1,530)		7,947
Interest expense	582		1,097
Other (income), net	472		(288)
Income (loss) before income tax expense	(2,584)		7,138
Income tax expense	(2,314)		3,401
Net income (loss)	(270)	$ (3,443)	3,737
Net (income) attributable to non-controlling interest	88		(1,002)
Net income (loss) attributable to SPAR Group, Inc.	$ (182)		$ 2,735
Basic earnings (loss) per common share attributable to SPAR Group, Inc. (in dollars per share)	$ (0.01)		$ 0.12
Diluted earnings (loss) per common share attributable to SPAR Group, Inc. (in dollars per share)	$ (0.01)		$ 0.11
Weighted average common shares – basic (in shares)	23,435		23,670
Weighted average common shares – diluted (in shares)	23,435		23,873
Foreign currency translation adjustments	$ (72)		$ (1,148)
Comprehensive income (loss)	(342)		2,589
Comprehensive (income) attributable to non-controlling interest	45		97
Comprehensive income (loss) attributable to SPAR Group, Inc.	(297)		2,686
Previously Reported [Member]
Net revenues	37,788	57,290	125,984
Related Party - Cost of revenues	0	0	0
Cost of revenues	29,346	46,297	102,448
Gross profit	8,442	10,993	23,536
Selling, general and administrative expense	8,558	9,541	19,158
(Gain) Loss on disposal of business	922	(4,919)	(12,076)	(11,154)
Depreciation and amortization	454	478	989
Operating income (loss)	(1,492)	5,893	15,465
Interest expense	582	567	1,097
Other (income), net	472	(296)	(288)
Income (loss) before income tax expense	(2,546)	5,622	14,656
Income tax expense	(2,314)	1,547	3,401
Net income (loss)	(232)	4,075	11,255	11,024
Net (income) attributable to non-controlling interest	88	(448)	(1,002)
Net income (loss) attributable to SPAR Group, Inc.	$ (144)	$ 3,627	$ 10,253
Basic earnings (loss) per common share attributable to SPAR Group, Inc. (in dollars per share)	$ (0.01)	$ 0.15	$ 0.43
Diluted earnings (loss) per common share attributable to SPAR Group, Inc. (in dollars per share)	$ (0.01)	$ 0.15	$ 0.43
Weighted average common shares – basic (in shares)	23,435	23,786	23,670
Weighted average common shares – diluted (in shares)	23,435	24,010	23,873
Foreign currency translation adjustments	$ (72)	$ 1,372	$ (1,148)
Comprehensive income (loss)	(304)	5,447	10,107
Comprehensive (income) attributable to non-controlling interest	45	(393)	97
Comprehensive income (loss) attributable to SPAR Group, Inc.	(259)	5,054	10,204
Previously Reported [Member] | Approximation [Member]
Net revenues				163,771
Related Party - Cost of revenues				0
Cost of revenues				131,801
Gross profit				31,970
Selling, general and administrative expense				27,707
(Gain) Loss on disposal of business				(11,154)
Depreciation and amortization				1,443
Operating income (loss)				13,974
Interest expense				1,678
Other (income), net				184
Income (loss) before income tax expense				12,112
Income tax expense				1,088
Net income (loss)				11,024
Net (income) attributable to non-controlling interest				(914)
Net income (loss) attributable to SPAR Group, Inc.				$ 10,110
Basic earnings (loss) per common share attributable to SPAR Group, Inc. (in dollars per share)				$ 0.43
Diluted earnings (loss) per common share attributable to SPAR Group, Inc. (in dollars per share)				$ 0.43
Weighted average common shares – basic (in shares)				23,591
Weighted average common shares – diluted (in shares)				23,768
Foreign currency translation adjustments				$ (1,220)
Comprehensive income (loss)				9,804
Comprehensive (income) attributable to non-controlling interest				142
Comprehensive income (loss) attributable to SPAR Group, Inc.				9,946
Revision of Prior Period, Adjustment [Member]
Net revenues	0	0	0
Related Party - Cost of revenues	0	0	0
Cost of revenues	0	0	0
Gross profit	0	0	0
Selling, general and administrative expense	0	0	0
(Gain) Loss on disposal of business	38	7,518	7,518	7,556
Depreciation and amortization	0	0	0
Operating income (loss)	(38)	(7,518)	(7,518)
Interest expense	0	0	0
Other (income), net	0	0	0
Income (loss) before income tax expense	(38)	(7,518)	(7,518)
Income tax expense	0	0	0
Net income (loss)	(38)	(7,518)	(7,518)	(7,556)
Net (income) attributable to non-controlling interest	0	0	0
Net income (loss) attributable to SPAR Group, Inc.	$ (38)	$ (7,518)	$ (7,518)
Basic earnings (loss) per common share attributable to SPAR Group, Inc. (in dollars per share)	$ (0)	$ (0.32)	$ (0.32)
Diluted earnings (loss) per common share attributable to SPAR Group, Inc. (in dollars per share)	$ (0)	$ (0.31)	$ (0.31)
Weighted average common shares – basic (in shares)	23,435	23,786	23,670
Weighted average common shares – diluted (in shares)	23,435	24,010	23,873
Foreign currency translation adjustments	$ 0	$ 0	$ 0
Comprehensive income (loss)	(38)	(7,518)	(7,518)
Comprehensive (income) attributable to non-controlling interest	0	0	0
Comprehensive income (loss) attributable to SPAR Group, Inc.	$ (38)	(7,518)	$ (7,518)
Revision of Prior Period, Adjustment [Member] | Approximation [Member]
Net revenues				0
Related Party - Cost of revenues				0
Cost of revenues				0
Gross profit				0
Selling, general and administrative expense				0
(Gain) Loss on disposal of business				7,556
Depreciation and amortization				0
Operating income (loss)				(7,556)
Interest expense				0
Other (income), net				0
Income (loss) before income tax expense				(7,556)
Income tax expense				0
Net income (loss)				(7,556)
Net (income) attributable to non-controlling interest				0
Net income (loss) attributable to SPAR Group, Inc.				$ (7,556)
Basic earnings (loss) per common share attributable to SPAR Group, Inc. (in dollars per share)				$ (0.32)
Diluted earnings (loss) per common share attributable to SPAR Group, Inc. (in dollars per share)				$ (0.32)
Weighted average common shares – basic (in shares)				23,591
Weighted average common shares – diluted (in shares)				23,768
Foreign currency translation adjustments				$ 0
Comprehensive income (loss)				(7,556)
Comprehensive (income) attributable to non-controlling interest				0
Comprehensive income (loss) attributable to SPAR Group, Inc.				(7,556)
Restated Amounts [Member]
Net revenues		57,290
Related Party - Cost of revenues		0
Cost of revenues		46,297
Gross profit		10,993
Selling, general and administrative expense		9,541
(Gain) Loss on disposal of business		2,599
Depreciation and amortization		478
Operating income (loss)		(1,625)
Interest expense		567
Other (income), net		(296)
Income (loss) before income tax expense		(1,896)
Income tax expense		1,547
Net income (loss)		(3,443)
Net (income) attributable to non-controlling interest		(448)
Net income (loss) attributable to SPAR Group, Inc.		$ (3,891)
Basic earnings (loss) per common share attributable to SPAR Group, Inc. (in dollars per share)		$ (0.16)
Diluted earnings (loss) per common share attributable to SPAR Group, Inc. (in dollars per share)		$ (0.16)
Weighted average common shares – basic (in shares)		23,786
Weighted average common shares – diluted (in shares)		24,010
Foreign currency translation adjustments		$ 1,372
Comprehensive income (loss)		(2,071)
Comprehensive (income) attributable to non-controlling interest		(393)
Comprehensive income (loss) attributable to SPAR Group, Inc.		$ (2,464)
Restated Amounts [Member] | Approximation [Member]
Net revenues				163,771
Related Party - Cost of revenues				0
Cost of revenues				131,801
Gross profit				31,970
Selling, general and administrative expense				27,707
(Gain) Loss on disposal of business				(3,598)
Depreciation and amortization				1,443
Operating income (loss)				6,418
Interest expense				1,678
Other (income), net				184
Income (loss) before income tax expense				4,556
Income tax expense				1,088
Net income (loss)				3,468
Net (income) attributable to non-controlling interest				(914)
Net income (loss) attributable to SPAR Group, Inc.				$ 2,554
Basic earnings (loss) per common share attributable to SPAR Group, Inc. (in dollars per share)				$ 0.11
Diluted earnings (loss) per common share attributable to SPAR Group, Inc. (in dollars per share)				$ 0.11
Weighted average common shares – basic (in shares)				23,591
Weighted average common shares – diluted (in shares)				23,768
Foreign currency translation adjustments				$ (1,220)
Comprehensive income (loss)				2,248
Comprehensive (income) attributable to non-controlling interest				142
Comprehensive income (loss) attributable to SPAR Group, Inc.				$ 2,390