Net Income (Loss) Per Common Unit (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Net Income per Common Unit [Abstract]
Net Income (Loss) Attributable to Genesis Energy L.P.	$ (416,678)	$ 95,999	$ (6,075)
Less: Accumulated distributions attributable to Class A Convertible Preferred Units	(74,736)	(74,467)	(69,801)
Net Income (Loss) Available to Common Unitholders	$ (491,414)	$ 21,532	$ (75,876)
Weighted Average Outstanding Units (in units)	122,579	122,579	122,579
Basic and Diluted (in dollars per unit)	$ (4.01)	$ 0.18	$ (0.62)