Acquisition (Schedule of Pro Forma Information) (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
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
As reported net income per unit (in dollars per share)	$ (0.15)	$ 0.01	$ (0.27)	$ 0.51
Alkali Business
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Revenues		$ 615,289		$ 1,829,389
Net Income Attributable to Genesis Energy, L.P.		10,955		92,880
Net Income (Loss) Available to Common Unitholders		$ (6,178)		$ 42,575
As reported net income per unit (in dollars per share)		$ 0.01		$ 0.51
Pro forma net income per unit (in dollars per share)		$ (0.05)		$ 0.35