Condensed Consolidating Financial Information (Condensed Consolidating Statement of Cash Flows) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Financial Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	$ 338,858	$ 298,338	$ 289,536
CASH FLOWS FROM OPERATING ACTIVITIES:
Payments to acquire fixed and intangible assets	(250,593)	(463,100)	(495,774)
Cash distributions received from equity investees - return of investment	20,280	21,353	25,645
Investments in equity investees	(4,647)	0	(3,045)
Acquisitions	(1,325,759)	(25,394)	(1,520,299)
Intercompany transfers	0	0	0
Repayments on loan to non-guarantor subsidiary	0	0	0
Contributions in aid of construction costs	124	13,374	3,179
Proceeds from asset sales	85,722	3,609	2,811
Other, net	0	(151)	(1,976)
Net cash used in investing activities	(1,474,873)	(450,309)	(1,989,459)
CASH FLOWS FROM FINANCING ACTIVITIES:
Borrowings on senior secured credit facility	1,458,700	1,115,800	1,525,050
Repayments on senior secured credit facility	(1,637,700)	(952,600)	(960,450)
Proceeds from issuance of senior unsecured notes	1,000,000	0	1,139,718
Proceeds from issuance of Class A convertible preferred units, net	726,419	0	0
Repayment of senior unsecured notes	(204,830)	0	(350,000)
Debt issuance costs	(25,913)	(1,578)	(28,901)
Intercompany transfers	0	0	0
Issuance of common units for cash, net	140,513	298,020	633,759
Distributions to partners/owners	(321,875)	(310,039)	(256,389)
Contributions (distributions) from (to) noncontrolling interests	2,770	236	(960)
Other, net	(57)	(1,734)	(471)
Net cash provided by financing activities	1,138,027	148,105	1,701,356
Net decrease in cash and cash equivalents	2,012	(3,866)	1,433
Cash and cash equivalents at beginning of period	7,029	10,895	9,462
Cash and cash equivalents at end of period	9,041	7,029	10,895
Reportable Legal Entities | Genesis Energy Finance Corporation (Co-Issuer)
Condensed Financial Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	0	0	0
CASH FLOWS FROM OPERATING ACTIVITIES:
Payments to acquire fixed and intangible assets	0	0	0
Cash distributions received from equity investees - return of investment	0	0	0
Investments in equity investees	0	0	0
Acquisitions	0	0	0
Intercompany transfers	0	0	0
Repayments on loan to non-guarantor subsidiary	0	0	0
Contributions in aid of construction costs	0	0	0
Proceeds from asset sales	0	0	0
Other, net	0	0	0
Net cash used in investing activities	0	0	0
CASH FLOWS FROM FINANCING ACTIVITIES:
Borrowings on senior secured credit facility	0	0	0
Repayments on senior secured credit facility	0	0	0
Proceeds from issuance of senior unsecured notes	0		0
Proceeds from issuance of Class A convertible preferred units, net	0
Repayment of senior unsecured notes	0		0
Debt issuance costs	0	0	0
Intercompany transfers	0	0	0
Issuance of common units for cash, net	0	0	0
Distributions to partners/owners	0	0	0
Contributions (distributions) from (to) noncontrolling interests	0	0	0
Other, net	0	0	0
Net cash provided by financing activities	0	0	0
Net decrease in cash and cash equivalents	0	0	0
Cash and cash equivalents at beginning of period	0	0	0
Cash and cash equivalents at end of period	0	0	0
Eliminations
Condensed Financial Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	(301,264)	(289,421)	(49,651)
CASH FLOWS FROM OPERATING ACTIVITIES:
Payments to acquire fixed and intangible assets	0	0	0
Cash distributions received from equity investees - return of investment	0	0	(186,026)
Investments in equity investees	140,513	298,020	633,761
Acquisitions	0	0	0
Intercompany transfers	1,157,781	31,436	1,240,973
Repayments on loan to non-guarantor subsidiary	(6,764)	(6,113)	(5,524)
Contributions in aid of construction costs	0	0	0
Proceeds from asset sales	0	0	0
Other, net	0	0	0
Net cash used in investing activities	1,291,530	323,343	1,683,184
CASH FLOWS FROM FINANCING ACTIVITIES:
Borrowings on senior secured credit facility	0	0	0
Repayments on senior secured credit facility	0	0	0
Proceeds from issuance of senior unsecured notes	0		0
Proceeds from issuance of Class A convertible preferred units, net	0
Repayment of senior unsecured notes	0		0
Debt issuance costs	0	0	0
Intercompany transfers	(1,157,781)	(31,437)	(1,240,973)
Issuance of common units for cash, net	(140,513)	(298,020)	(633,759)
Distributions to partners/owners	321,875	310,039	256,389
Contributions (distributions) from (to) noncontrolling interests	0	0	0
Other, net	(13,847)	(14,504)	(15,190)
Net cash provided by financing activities	(990,266)	(33,922)	(1,633,533)
Net decrease in cash and cash equivalents	0	0	0
Cash and cash equivalents at beginning of period	0	0	0
Cash and cash equivalents at end of period	0	0	0
Genesis Energy, L.P. (Parent and Co-Issuer) | Reportable Legal Entities
Condensed Financial Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	162,980	179,853	(14,082)
CASH FLOWS FROM OPERATING ACTIVITIES:
Payments to acquire fixed and intangible assets	0	0	0
Cash distributions received from equity investees - return of investment	0	0	186,026
Investments in equity investees	(140,513)	(298,020)	(633,761)
Acquisitions	0	0	0
Intercompany transfers	(1,157,781)	(31,436)	(1,240,973)
Repayments on loan to non-guarantor subsidiary	0	0	0
Contributions in aid of construction costs	0	0	0
Proceeds from asset sales	0	0	0
Other, net	0	0	0
Net cash used in investing activities	(1,298,294)	(329,456)	(1,688,708)
CASH FLOWS FROM FINANCING ACTIVITIES:
Borrowings on senior secured credit facility	1,458,700	1,115,800	1,525,050
Repayments on senior secured credit facility	(1,637,700)	(952,600)	(960,450)
Proceeds from issuance of senior unsecured notes	1,000,000		1,139,718
Proceeds from issuance of Class A convertible preferred units, net	726,419
Repayment of senior unsecured notes	(204,830)		(350,000)
Debt issuance costs	(25,913)	(1,578)	(28,901)
Intercompany transfers	0	0	0
Issuance of common units for cash, net	140,513	298,020	633,759
Distributions to partners/owners	(321,875)	(310,039)	(256,389)
Contributions (distributions) from (to) noncontrolling interests	0	0	0
Other, net	0	0	0
Net cash provided by financing activities	1,135,314	149,603	1,702,787
Net decrease in cash and cash equivalents	0	0	(3)
Cash and cash equivalents at beginning of period	6	6	9
Cash and cash equivalents at end of period	6	6	6
Guarantor Subsidiaries | Reportable Legal Entities
Condensed Financial Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	481,727	398,320	308,144
CASH FLOWS FROM OPERATING ACTIVITIES:
Payments to acquire fixed and intangible assets	(250,593)	(463,100)	(495,774)
Cash distributions received from equity investees - return of investment	20,280	21,353	25,645
Investments in equity investees	(4,647)	0	(3,045)
Acquisitions	(1,325,759)	(25,394)	(1,520,299)
Intercompany transfers	0	0	0
Repayments on loan to non-guarantor subsidiary	6,764	6,113	5,524
Contributions in aid of construction costs	124	13,374	3,179
Proceeds from asset sales	85,722	3,609	2,811
Other, net	0	(151)	(1,976)
Net cash used in investing activities	(1,468,109)	(444,196)	(1,983,935)
CASH FLOWS FROM FINANCING ACTIVITIES:
Borrowings on senior secured credit facility	0	0	0
Repayments on senior secured credit facility	0	0	0
Proceeds from issuance of senior unsecured notes	0		0
Proceeds from issuance of Class A convertible preferred units, net	0
Repayment of senior unsecured notes	0		0
Debt issuance costs	0	0	0
Intercompany transfers	1,169,781	57,701	1,299,830
Issuance of common units for cash, net	140,513	298,020	633,759
Distributions to partners/owners	(321,875)	(310,039)	(256,389)
Contributions (distributions) from (to) noncontrolling interests	0	0	(960)
Other, net	(57)	(1,734)	(471)
Net cash provided by financing activities	988,362	43,948	1,675,769
Net decrease in cash and cash equivalents	1,980	(1,928)	(22)
Cash and cash equivalents at beginning of period	6,360	8,288	8,310
Cash and cash equivalents at end of period	8,340	6,360	8,288
Non-Guarantor Subsidiaries | Reportable Legal Entities
Condensed Financial Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	(4,585)	9,586	45,125
CASH FLOWS FROM OPERATING ACTIVITIES:
Payments to acquire fixed and intangible assets	0	0	0
Cash distributions received from equity investees - return of investment	0	0	0
Investments in equity investees	0	0	0
Acquisitions	0	0	0
Intercompany transfers	0	0	0
Repayments on loan to non-guarantor subsidiary	0	0	0
Contributions in aid of construction costs	0	0	0
Proceeds from asset sales	0	0	0
Other, net	0	0	0
Net cash used in investing activities	0	0	0
CASH FLOWS FROM FINANCING ACTIVITIES:
Borrowings on senior secured credit facility	0	0	0
Repayments on senior secured credit facility	0	0	0
Proceeds from issuance of senior unsecured notes	0		0
Proceeds from issuance of Class A convertible preferred units, net	0
Repayment of senior unsecured notes	0		0
Debt issuance costs	0	0	0
Intercompany transfers	(12,000)	(26,264)	(58,857)
Issuance of common units for cash, net	0	0	0
Distributions to partners/owners	0	0	0
Contributions (distributions) from (to) noncontrolling interests	2,770	236	0
Other, net	13,847	14,504	15,190
Net cash provided by financing activities	4,617	(11,524)	(43,667)
Net decrease in cash and cash equivalents	32	(1,938)	1,458
Cash and cash equivalents at beginning of period	663	2,601	1,143
Cash and cash equivalents at end of period	$ 695	$ 663	$ 2,601