SEGMENT AND GEOGRAPHIC DATA - Segment Information (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($) Segment	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | Segment			3
Revenue, from external customers	$ 56,723	$ 39,674	$ 108,640	$ 74,135
Inter-segment revenue	0	0	0	0
Revenue	56,723	39,674	108,640	74,135
Adjusted net revenue, from external customers	27,274	15,091	52,847	27,809
Inter-segment adjusted net revenue	0	0	0	0
Total adjusted net revenue	27,274	15,091	52,847	27,809
EBITDA (loss)	4,208	371	8,085	446
Depreciation and amortization	(337)	(113)	(661)	(223)
Intercompany dividend/interest (expense) income, net	0	0	0	0
Interest income, net	3	9	5	19
Income before income taxes	3,874	267	7,429	242
Provision for income taxes	(781)	(389)	(1,317)	(567)
Net income (loss)	3,093	(122)	6,112	(325)
Accounts receivable, net	31,646	25,748	31,646	25,748	$ 25,748
Long-lived assets, net of accumulated depreciation and amortization	9,598	10,078	9,598	10,078
Total assets	71,660	61,242	71,660	61,242	$ 61,242
Inter-Segment Elimination
Segment Reporting Information [Line Items]
Revenue, from external customers	0	0	0	0
Inter-segment revenue	(53)	(15)	(149)	(15)
Revenue	(53)	(15)	(149)	(15)
Adjusted net revenue, from external customers	0	0	0	0
Inter-segment adjusted net revenue	4	0	4	0
Total adjusted net revenue	4	0	4	0
EBITDA (loss)	0	0	0	0
Depreciation and amortization	0	0	0	0
Intercompany dividend/interest (expense) income, net	(2,433)	0	(2,433)	0
Interest income, net	0	0	0	0
Provision for income taxes	0	0	0	0
Net income (loss)	(2,433)	0	(2,433)	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	14,415	5,366	29,026	9,927
Inter-segment revenue	46	0	99	0
Revenue	14,461	5,366	29,125	9,927
Adjusted net revenue, from external customers	13,809	4,993	27,511	9,202
Inter-segment adjusted net revenue	45	(15)	61	(15)
Total adjusted net revenue	13,854	4,978	27,572	9,187
EBITDA (loss)	2,291	(173)	4,705	(451)
Depreciation and amortization	(321)	(87)	(626)	(173)
Intercompany dividend/interest (expense) income, net	0	0	0	0
Interest income, net	0	0	0	0
Provision for income taxes	(26)	(8)	(68)	(17)
Net income (loss)	1,944	(268)	4,011	(641)
Accounts receivable, net	11,531	8,765	11,531	8,765
Long-lived assets, net of accumulated depreciation and amortization	9,479	9,964	9,479	9,964
Total assets	26,543	22,214	26,543	22,214
Hudson Asia Pacific | Operating Segments
Segment Reporting Information [Line Items]
Revenue, from external customers	29,944	28,801	61,077	54,141
Inter-segment revenue	0	15	12	15
Revenue	29,944	28,816	61,089	54,156
Adjusted net revenue, from external customers	9,174	6,880	17,387	12,638
Inter-segment adjusted net revenue	(45)	15	(53)	15
Total adjusted net revenue	9,129	6,895	17,334	12,653
EBITDA (loss)	2,262	1,003	4,289	1,765
Depreciation and amortization	(9)	(17)	(20)	(31)
Intercompany dividend/interest (expense) income, net	(81)	(86)	(156)	(171)
Interest income, net	1	1	2	2
Provision for income taxes	(544)	(243)	(1,075)	(437)
Net income (loss)	1,629	658	3,040	1,128
Accounts receivable, net	13,557	12,073	13,557	12,073
Long-lived assets, net of accumulated depreciation and amortization	67	68	67	68
Total assets	24,072	21,744	24,072	21,744
Hudson Europe | Operating Segments
Segment Reporting Information [Line Items]
Revenue, from external customers	12,364	5,507	18,537	10,067
Inter-segment revenue	7	0	38	0
Revenue	12,371	5,507	18,575	10,067
Adjusted net revenue, from external customers	4,291	3,218	7,949	5,969
Inter-segment adjusted net revenue	(4)	0	(12)	0
Total adjusted net revenue	4,287	3,218	7,937	5,969
EBITDA (loss)	551	476	698	546
Depreciation and amortization	(6)	(8)	(13)	(17)
Intercompany dividend/interest (expense) income, net	1,214	0	1,214	0
Interest income, net	0	0	0	0
Provision for income taxes	(92)	(123)	(76)	(140)
Net income (loss)	1,667	345	1,823	389
Accounts receivable, net	6,332	4,910	6,332	4,910
Long-lived assets, net of accumulated depreciation and amortization	50	42	50	42
Total assets	13,008	9,370	13,008	9,370
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)	(896)	(935)	(1,607)	(1,414)
Depreciation and amortization	(1)	(1)	(2)	(2)
Intercompany dividend/interest (expense) income, net	1,300	86	1,375	171
Interest income, net	2	8	3	17
Provision for income taxes	(119)	(15)	(98)	27
Net income (loss)	286	(857)	(329)	(1,201)
Accounts receivable, net	226	0	226	0
Long-lived assets, net of accumulated depreciation and amortization	2	4	2	4
Total assets	$ 8,037	$ 7,914	$ 8,037	$ 7,914