Net Income Per Common Unit (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Earnings Per Share Reconciliation [Abstract]
Net Income Attributable to Genesis Energy L.P.	$ 8,034	$ 27,090
Less: Accumulated distributions attributable to Class A Convertible Preferred Units	(16,888)	0
Net Income (loss) Available to Common Unitholders	$ (8,854)	$ 27,090
Weighted Average Outstanding Shares (in shares)	122,579,000	118,388,000
Basic and Diluted Net Income per Common Unit (in dollars per unit)	$ (0.07)	$ 0.23
Alkali Business
Earnings Per Share Reconciliation [Abstract]
Basic and Diluted Net Income per Common Unit (in dollars per unit)		$ 0.23
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)	22,901,980