CONSOLIDATED STATEMENT OF STOCKHOLDERS’ EQUITY - USD ($) shares in Thousands, $ in Thousands	Common Stock	Additional Paid In Capital [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Loss [Member]	Accumulated Deficit [Member]	Total
Balance at Dec. 31, 2014	$ 38	$ 204,525	$ (5,244)	$ (4,582)	$ (154,020)	$ 40,717
Balance (in shares) at Dec. 31, 2014	37,943
Increase (Decrease) in Stockholders' Equity
Net income attributable to ISG					4,841	4,841
Other comprehensive income (loss)				(1,956)		(1,956)
Equity securities repurchased		2	(3,383)			(3,381)
Proceeds from issuance of ESPP		(80)	661			581
Issuance of treasury shares		(4,913)	4,913
Accretion of noncontrolling interest		(78)				(78)
Dividend paid		(61)				(61)
Acquisition		150				150
Acquisition (in shares)	34
Tax benefit on stock issuance		310				310
Stock based compensation		5,049				5,049
Balance at Dec. 31, 2015	$ 38	204,904	(3,053)	(6,538)	(149,179)	46,172
Balance (in shares) at Dec. 31, 2015	37,977
Increase (Decrease) in Stockholders' Equity
Net income attributable to ISG					(6,505)	(6,505)
Other comprehensive income (loss)				(1,262)		(1,262)
Equity securities repurchased			(11,565)			(11,565)
Proceeds from issuance of ESPP		(74)	635			561
Issuance of treasury shares		(5,767)	5,767
Accretion of noncontrolling interest		(309)				(309)
Issuance of common stock for earnout		100				100
Issuance of common stock for earnout (in shares)	26
Issuance of common stock	$ 3	11,997				12,000
Issuance of common stock (in shares)	3,000
Acquisition	$ 3	10,941				10,944
Acquisition (in shares)	3,200
Tax benefit on stock issuance		(147)				(147)
Stock based compensation		7,047				7,047
Balance at Dec. 31, 2016	$ 44	228,692	(8,216)	(7,800)	(155,684)	$ 57,036
Balance (in shares) at Dec. 31, 2016	44,203					44,203
Increase (Decrease) in Stockholders' Equity
Net income attributable to ISG					(2,130)	$ (2,130)
Other comprehensive income (loss)				2,134		2,134
Equity securities repurchased			(2,853)			(2,853)
Proceeds from issuance of ESPP		(136)	808			672
Issuance of treasury shares		(7,100)	7,100
Accretion of noncontrolling interest		30				30
Issuance of common stock for earnout		721				721
Issuance of common stock for earnout (in shares)	287
Purchase of non-controlling interest		488				488
Stock based compensation		7,439				7,439
Balance at Dec. 31, 2017	$ 44	$ 230,134	$ (3,161)	$ (5,666)	$ (157,814)	$ 63,537
Balance (in shares) at Dec. 31, 2017	44,490					44,490