Net Income Per Common Unit (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share Reconciliation [Abstract]
Net Income (Loss) Attributable to Genesis Energy L.P.	$ (323)	$ 6,312	$ 18,708	$ 67,135
Less: Accumulated distributions attributable to Class A Convertible Preferred Units	(17,635)	(5,469)	(51,780)	(5,469)
Net Income (Loss) Available to Common Unitholders	$ (17,958)	$ 843	$ (33,072)	$ 61,666
Weighted Average Outstanding Shares (in shares)	122,579,000	122,579,000	122,579,000	121,198,000
Basic and Diluted Net Income per Common Unit (in dollars per unit)	$ (0.15)	$ 0.01	$ (0.27)	$ 0.51
Class A Convertible Preferred Stock Units
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Antidilutive securities not included in computation of dilutive earnings (in shares)	23,914,890		23,914,890