SEGMENT AND GEOGRAPHIC DATA - Segment Information (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) Segment	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | Segment			3
Revenue, from external customers	$ 36,853	$ 39,398	$ 106,456	$ 127,367
Inter-segment revenue	0	0	0	0
Revenue	36,853	39,398	106,456	127,367
Adjusted net revenue, from external customers	18,603	19,370	52,548	63,717
Inter-segment adjusted net revenue	0	0	0	0
Total adjusted net revenue	18,603	19,370	52,548	63,717
EBITDA (loss)	(283)	1,247	(2,960)	3,405
Depreciation and amortization	(358)	(374)	(1,042)	(1,076)
Intercompany dividend/interest (expense) income, net	0	0	0	0
Interest income, net	93	90	280	284
(Loss) income before income taxes	(548)	963	(3,722)	2,613
Provision for income taxes	(298)	(430)	(463)	(1,148)
Net (loss) income	(846)	533	(4,185)	1,465
Accounts receivable, net	24,475	19,710	24,475	19,710	$ 19,710
Long-lived assets, net of accumulated depreciation and amortization	8,831	9,798	8,831	9,798
Total assets	57,154	60,958	57,154	60,958	$ 60,958
Inter-Segment Elimination
Segment Reporting Information [Line Items]
Revenue, from external customers	0	0	0	0
Inter-segment revenue	(37)	(137)	(185)	(224)
Revenue	(37)	(137)	(185)	(224)
Adjusted net revenue, from external customers	0	0	0	0
Inter-segment adjusted net revenue	0	9	0	(17)
Total adjusted net revenue	0	9	0	(17)
EBITDA (loss)	0	0	0	0
Depreciation and amortization	0	0	0	0
Intercompany dividend/interest (expense) income, net	0	0	0	(1,218)
Interest income, net	0	0	0	0
Provision for income taxes	0	0	0	0
Net (loss) income	0	0	0	(1,218)
Accounts receivable, net	0	0	0	0
Long-lived assets, net of accumulated depreciation and amortization	0	0	0	0
Total assets	0	0	0	0
Hudson Americas | Operating Segments
Segment Reporting Information [Line Items]
Revenue, from external customers	7,578	7,167	20,544	25,008
Inter-segment revenue	28	119	142	230
Revenue	7,606	7,286	20,686	25,238
Adjusted net revenue, from external customers	6,634	6,854	18,783	24,097
Inter-segment adjusted net revenue	29	119	142	230
Total adjusted net revenue	6,663	6,973	18,925	24,327
EBITDA (loss)	351	20	(111)	(876)
Depreciation and amortization	(308)	(313)	(889)	(936)
Intercompany dividend/interest (expense) income, net	0	0	0	0
Interest income, net	0	0	0	0
Provision for income taxes	(44)	(44)	(111)	111
Net (loss) income	(1)	(337)	(1,111)	(1,701)
Accounts receivable, net	5,103	5,502	5,103	5,502
Long-lived assets, net of accumulated depreciation and amortization	6,908	7,773	6,908	7,773
Total assets	14,199	17,632	14,199	17,632
Hudson Asia Pacific | Operating Segments
Segment Reporting Information [Line Items]
Revenue, from external customers	22,560	26,106	66,718	81,784
Inter-segment revenue	1	0	1	0
Revenue	22,561	26,106	66,719	81,784
Adjusted net revenue, from external customers	7,847	8,694	22,020	26,734
Inter-segment adjusted net revenue	(27)	(109)	(166)	(147)
Total adjusted net revenue	7,820	8,585	21,854	26,587
EBITDA (loss)	312	1,890	(65)	5,455
Depreciation and amortization	(40)	(52)	(124)	(111)
Intercompany dividend/interest (expense) income, net	(134)	(128)	(397)	(375)
Interest income, net	2	2	7	6
Provision for income taxes	(111)	(520)	90	(1,440)
Net (loss) income	29	1,192	(489)	3,535
Accounts receivable, net	12,315	9,280	12,315	9,280
Long-lived assets, net of accumulated depreciation and amortization	1,865	1,954	1,865	1,954
Total assets	24,269	23,604	24,269	23,604
Hudson Europe | Operating Segments
Segment Reporting Information [Line Items]
Revenue, from external customers	6,715	6,125	19,194	20,575
Inter-segment revenue	8	18	42	(6)
Revenue	6,723	6,143	19,236	20,569
Adjusted net revenue, from external customers	4,122	3,822	11,745	12,886
Inter-segment adjusted net revenue	(2)	(19)	24	(66)
Total adjusted net revenue	4,120	3,803	11,769	12,820
EBITDA (loss)	42	(300)	459	995
Depreciation and amortization	(6)	(7)	(20)	(22)
Intercompany dividend/interest (expense) income, net	0	0	0	1,218
Interest income, net	0	0	0	0
Provision for income taxes	(94)	26	(347)	(387)
Net (loss) income	(58)	(281)	92	1,804
Accounts receivable, net	7,057	4,928	7,057	4,928
Long-lived assets, net of accumulated depreciation and amortization	27	33	27	33
Total assets	11,356	11,064	11,356	11,064
Corporate Segment | Operating Segments
Segment Reporting Information [Line Items]
Revenue, from external customers	0	0	0	0
Inter-segment revenue	0	0	0	0
Revenue	0	0	0	0
Adjusted net revenue, from external customers	0	0	0	0
Inter-segment adjusted net revenue	0	0	0	0
Total adjusted net revenue	0	0	0	0
EBITDA (loss)	(988)	(363)	(3,243)	(2,169)
Depreciation and amortization	(4)	(2)	(9)	(7)
Intercompany dividend/interest (expense) income, net	134	128	397	375
Interest income, net	91	88	273	278
Provision for income taxes	(49)	108	(95)	568
Net (loss) income	(816)	(41)	(2,677)	(955)
Accounts receivable, net	0	0	0	0
Long-lived assets, net of accumulated depreciation and amortization	31	38	31	38
Total assets	$ 7,330	$ 8,658	$ 7,330	$ 8,658