Net Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Earnings Per Share [Abstract]
Net loss attributable to Clean Energy Fuels Corp.	$ (6,736)	$ (5,383)	$ (5,032)	$ (16,329)
Weighted average common shares outstanding	200,670,137	204,653,723	202,831,346	204,426,459
Weighted average common shares outstanding - diluted	200,670,137	204,653,723	202,831,346	204,426,459
Basic and diluted loss per share	$ (0.03)	$ (0.03)	$ (0.02)	$ (0.08)