CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (47,214)	$ (70,398)	$ (29,377)
Other comprehensive income (loss), net of taxes, as appropriate:
Foreign currency translation adjustments	1,124	(1,563)	2,869
Comprehensive net loss	(46,090)	(71,961)	(26,508)
Comprehensive income attributable to noncontrolling interests	(985)	(773)	(865)
Comprehensive net loss attributable to ION	$ (47,075)	$ (72,734)	$ (27,373)