CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net loss before noncontrolling interest	$ (29,352)	$ (40,831)
Other comprehensive (loss) income:
Foreign currency translation adjustments	(2,843)	(3,927)
Unrealized foreign exchange (loss) gain on intercompany balance	(1,513)	4,303
Net unrealized (loss) gain on securities available-for-sale	(15)	7
Other comprehensive (loss) income	(4,371)	383
Comprehensive loss	(33,723)	(40,448)
Comprehensive loss attributable to noncontrolling interest	32	161
Comprehensive loss attributable to CTI	$ (33,691)	$ (40,287)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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