SEGMENT AND GEOGRAPHIC DATA Segment Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2017 USD ($) segments	Mar. 31, 2016 USD ($)	Dec. 31, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments | segments	3
Revenue, from external customers	$ 103,405	$ 101,227
Inter-segment revenue	0	0
Total revenue	103,405	101,227
Gross margin, from external customers	42,432	41,262
Inter-segment gross margin	0	0
Gross margin	42,432	41,262
Business reorganization	222	637
EBITDA (loss)	(440)	(3,154)
Depreciation and amortization	666	688
Intercompany interest income (expense), net	0	0
Interest income (expense), net	(88)	(54)
Income (loss) from continuing operations before provision for income taxes	(1,194)	(3,896)
Accounts receivable, net	66,781	64,208	$ 58,517
Long-lived assets, net of accumulated depreciation and amortization	8,941	9,949
Total assets	104,619	121,838	$ 101,812
Hudson Asia Pacific
Segment Reporting Information [Line Items]
Total revenue	9,523	7,956
Long-lived assets, net of accumulated depreciation and amortization	640	548
Hudson Europe
Segment Reporting Information [Line Items]
Total revenue	14,211	12,123
Long-lived assets, net of accumulated depreciation and amortization	244	167
Operating Segments | Hudson Americas
Segment Reporting Information [Line Items]
Revenue, from external customers	4,315	3,837
Inter-segment revenue	(1)	0
Total revenue	4,314	3,837
Gross margin, from external customers	3,836	3,341
Inter-segment gross margin	(4)	(2)
Gross margin	3,832	3,339
Business reorganization	(92)	(16)
EBITDA (loss)	334	162
Depreciation and amortization	2	22
Intercompany interest income (expense), net	0	0
Interest income (expense), net	0	0
Income (loss) from continuing operations before provision for income taxes	332	140
Accounts receivable, net	3,062	3,162
Long-lived assets, net of accumulated depreciation and amortization	0	28
Total assets	6,182	7,243
Operating Segments | Hudson Asia Pacific
Segment Reporting Information [Line Items]
Revenue, from external customers	59,710	51,071
Inter-segment revenue	1	0
Total revenue	59,711	51,071
Gross margin, from external customers	19,735	18,771
Inter-segment gross margin	(58)	(60)
Gross margin	19,677	18,711
Business reorganization	0	197
EBITDA (loss)	(726)	(1,231)
Depreciation and amortization	428	404
Intercompany interest income (expense), net	0	0
Interest income (expense), net	(96)	(40)
Income (loss) from continuing operations before provision for income taxes	(1,250)	(1,675)
Accounts receivable, net	36,221	31,331
Long-lived assets, net of accumulated depreciation and amortization	7,181	7,475
Total assets	55,467	51,313
Operating Segments | Hudson Europe
Segment Reporting Information [Line Items]
Revenue, from external customers	39,380	46,319
Inter-segment revenue	62	62
Total revenue	39,442	46,381
Gross margin, from external customers	18,861	19,150
Inter-segment gross margin	62	62
Gross margin	18,923	19,212
Business reorganization	336	484
EBITDA (loss)	880	(330)
Depreciation and amortization	157	183
Intercompany interest income (expense), net	(44)	(57)
Interest income (expense), net	9	(14)
Income (loss) from continuing operations before provision for income taxes	688	(584)
Accounts receivable, net	27,498	29,715
Long-lived assets, net of accumulated depreciation and amortization	1,472	1,851
Total assets	41,264	54,047
Corporate
Segment Reporting Information [Line Items]
Revenue, from external customers	0	0
Inter-segment revenue	0	0
Total revenue	0	0
Gross margin, from external customers	0	0
Inter-segment gross margin	0	0
Gross margin	0	0
Business reorganization	(22)	(28)
EBITDA (loss)	(928)	(1,755)
Depreciation and amortization	79	79
Intercompany interest income (expense), net	44	57
Interest income (expense), net	(1)	0
Income (loss) from continuing operations before provision for income taxes	(964)	(1,777)
Accounts receivable, net	0	0
Long-lived assets, net of accumulated depreciation and amortization	288	595
Total assets	1,706	9,235
Elimination
Segment Reporting Information [Line Items]
Revenue, from external customers	0	0
Inter-segment revenue	(62)	(62)
Total revenue	(62)	(62)
Gross margin, from external customers	0	0
Inter-segment gross margin	0	0
Gross margin	0	0
Business reorganization	0	0
EBITDA (loss)	0	0
Depreciation and amortization	0	0
Intercompany interest income (expense), net	0	0
Interest income (expense), net	0	0
Income (loss) from continuing operations before provision for income taxes	0	0
Accounts receivable, net	0	0
Long-lived assets, net of accumulated depreciation and amortization	0	0
Total assets	$ 0	$ 0