SEGMENT AND GEOGRAPHIC DATA - Segment Information (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($) Segment	Jun. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | Segment			3
Revenue, from external customers	$ 35,541	$ 35,712	$ 67,407	$ 69,603
Inter-segment revenue	0	0	0	0
Revenue	35,541	35,712	67,407	69,603
Adjusted net revenue, from external customers	18,635	17,615	35,033	33,945
Inter-segment adjusted net revenue	0	0	0	0
Total adjusted net revenue	18,635	17,615	35,033	33,945
Salaries and related	(14,837)	(14,325)	(29,182)	(29,491)
EBITDA (loss)	(152)	5	(1,664)	(2,677)
Depreciation and amortization	(245)	(287)	(528)	(684)
Intercompany dividend/interest (expense) income, net	0	0	0	0
Interest income, net	54	94	125	187
Loss before income taxes	(343)	(188)	(2,067)	(3,174)
Provision for income taxes	(345)	(253)	(377)	(165)
Net loss	(688)	(441)	(2,444)	(3,339)
Accounts receivable, net	23,549	20,093	23,549	20,093	$ 20,093
Long-lived assets, net of accumulated depreciation and amortization	8,027	8,436	8,027	8,436
Total assets	55,577	52,583	55,577	52,583	$ 52,583
Inter-Segment Elimination
Segment Reporting Information [Line Items]
Revenue, from external customers	0	0	0	0
Inter-segment revenue	(68)	(93)	(159)	(148)
Revenue	(68)	(93)	(159)	(148)
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
Salaries and related	0	0	0	0
EBITDA (loss)	0	0	0	0
Depreciation and amortization	0	0	0	0
Intercompany dividend/interest (expense) income, net	0	0	0	0
Interest income, net	0	0	0	0
Provision for income taxes	0	0	0	0
Net loss	0	0	0	0
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	7,138	6,972	13,990	12,966
Inter-segment revenue	68	59	158	114
Revenue	7,206	7,031	14,148	13,080
Adjusted net revenue, from external customers	6,299	6,344	12,279	12,149
Inter-segment adjusted net revenue	69	58	158	113
Total adjusted net revenue	6,368	6,402	12,437	12,262
Salaries and related	(4,689)	(4,893)	(9,507)	(10,247)
EBITDA (loss)	228	402	87	(462)
Depreciation and amortization	(204)	(232)	(445)	(581)
Intercompany dividend/interest (expense) income, net	0	0	0	0
Interest income, net	0	0	0	0
Provision for income taxes	(43)	(52)	(63)	(67)
Net loss	(19)	118	(421)	(1,110)
Accounts receivable, net	5,664	4,740	5,664	4,740
Long-lived assets, net of accumulated depreciation and amortization	6,190	6,640	6,190	6,640
Total assets	14,608	14,455	14,608	14,455
Hudson Asia Pacific | Operating Segments
Segment Reporting Information [Line Items]
Revenue, from external customers	21,570	22,649	40,697	44,158
Inter-segment revenue	0	0	1	0
Revenue	21,570	22,649	40,698	44,158
Adjusted net revenue, from external customers	8,839	7,627	16,050	14,173
Inter-segment adjusted net revenue	(69)	(92)	(157)	(139)
Total adjusted net revenue	8,770	7,535	15,893	14,034
Salaries and related	(6,061)	(6,072)	(11,779)	(12,063)
EBITDA (loss)	1,427	224	1,710	(377)
Depreciation and amortization	(35)	(46)	(70)	(84)
Intercompany dividend/interest (expense) income, net	(124)	(131)	(247)	(263)
Interest income, net	(33)	2	(31)	5
Provision for income taxes	(407)	(16)	(493)	201
Net loss	828	33	869	(518)
Accounts receivable, net	12,878	9,254	12,878	9,254
Long-lived assets, net of accumulated depreciation and amortization	1,796	1,744	1,796	1,744
Total assets	23,072	21,425	23,072	21,425
Hudson Europe | Operating Segments
Segment Reporting Information [Line Items]
Revenue, from external customers	6,833	6,091	12,720	12,479
Inter-segment revenue	0	34	0	34
Revenue	6,833	6,125	12,720	12,513
Adjusted net revenue, from external customers	3,497	3,644	6,704	7,623
Inter-segment adjusted net revenue	0	34	(1)	26
Total adjusted net revenue	3,497	3,678	6,703	7,649
Salaries and related	(3,710)	(3,062)	(7,068)	(6,417)
EBITDA (loss)	(701)	149	(1,339)	417
Depreciation and amortization	(4)	(7)	(8)	(14)
Intercompany dividend/interest (expense) income, net	0	0	0	0
Interest income, net	0	0	0	0
Provision for income taxes	78	(167)	108	(253)
Net loss	(627)	(25)	(1,239)	150
Accounts receivable, net	5,006	6,099	5,006	6,099
Long-lived assets, net of accumulated depreciation and amortization	19	26	19	26
Total assets	9,081	9,393	9,081	9,393
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
Salaries and related	(377)	(298)	(828)	(764)
EBITDA (loss)	(1,106)	(770)	(2,122)	(2,255)
Depreciation and amortization	(2)	(2)	(5)	(5)
Intercompany dividend/interest (expense) income, net	124	131	247	263
Interest income, net	87	92	156	182
Provision for income taxes	27	(18)	71	(46)
Net loss	(870)	(567)	(1,653)	(1,861)
Accounts receivable, net	1	0	1	0
Long-lived assets, net of accumulated depreciation and amortization	22	26	22	26
Total assets	$ 8,816	$ 7,310	$ 8,816	$ 7,310