Net Earnings (Loss) per Common Share - Basic and Diluted Net Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Net income (loss) attributable to shareholders of Manitex International, Inc.
Net income (loss) from continuing operations attributable to shareholders of Manitex International, Inc.	$ 122	$ (1,522)	$ (2,330)	$ (6,437)
(Loss) income from operations of discontinued operations, net of income taxes		(15)		532
Less: (income) attributable to noncontrolling interest from discontinued operations				(274)
(Loss) income from operations of discontinued operations attributable to shareholders of Manitex International, Inc., net of income taxes		(15)		258
Income (loss) on sale of discontinued operations, net of income taxes		30		(1,077)
Net income (loss) attributable to shareholders of Manitex International, Inc.	$ 122	$ (1,507)	$ (2,330)	$ (7,256)
Earnings (loss) per share Basic
Income (loss) from continuing operations attributable to shareholders of Manitex International, Inc.	$ 0.01	$ (0.09)	$ (0.13)	$ (0.39)
Earnings from operations of discontinued operations attributable to shareholders of Manitex International, Inc., net of income taxes				0.02
Loss on sale of discontinued operations attributable to shareholders' of Manitex international, net of income taxes				(0.07)
Net earnings (loss) attributable to shareholders of Manitex International, Inc.	0.01	(0.09)	(0.13)	(0.44)
Earnings (loss) per share Diluted
Income (loss) from continuing operations attributable to shareholders of Manitex International, Inc.	0.01	(0.09)	(0.13)	(0.39)
Earnings from operations of discontinued operations attributable to shareholders of Manitex International, Inc., net of income taxes				0.02
Loss attributable to shareholders of Manitex International, Inc.				(0.07)
Net earnings (loss) attributable to shareholders of Manitex International, Inc.	$ 0.01	$ (0.09)	$ (0.13)	$ (0.44)
Weighted average common shares outstanding
Basic	19,610,168	16,573,927	18,003,829	16,532,683
Diluted
Basic	19,610,168	16,573,927	18,003,829	16,532,683
Dilutive effect of restricted stock units and stock options	84,211
Diluted	19,694,379	16,573,927	18,003,829	16,532,683