Net Loss Attributable to ORBCOMM Inc. Common Stockholders - Summary of Basic and Diluted Calculations of EPS (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Earnings Per Share [Abstract]
Net loss attributable to ORBCOMM Inc. common stockholders	$ (7,233)	$ (10,740)	$ (17,319)	$ (14,083)
Weighted average number of common shares outstanding:
Basic number of common shares outstanding	78,079	71,978	76,404	71,703
Diluted number of common shares outstanding	78,079	71,978	76,404	71,703
Earnings per share:
Basic	$ (0.09)	$ (0.15)	$ (0.23)	$ (0.20)
Diluted	$ (0.09)	$ (0.15)	$ (0.23)	$ (0.20)