Condensed Consolidating Financial Information (Condensed Consolidating Statement of Cash Flows) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	$ 86,328	$ 61,040
Payments to acquire fixed and intangible assets	(66,051)	(61,292)
Cash distributions received from equity investees - return of investment	9,277	9,083
Investments in equity investees		0
Acquisitions	0	0
Intercompany transfers	0	0
Repayments on loan to non-guarantor subsidiary	0	0
Contributions in aid of construction costs	0	124
Proceeds from asset sales	6	1,234
Other, net	0	0
Net cash used in investing activities	(56,768)	(50,851)
Borrowings on senior secured credit facility	333,800	216,700
Repayments on senior secured credit facility	(154,000)	(284,900)
Proceeds from issuance of senior unsecured notes	0
Repayments of Unsecured Debt	145,170	0
Proceeds from issuance of Class A convertible preferred units, net	0
Debt issuance costs	(159)	0
Intercompany transfers	0	0
Issuance of common units for cash, net	0	140,968
Distributions to partners/owners	(62,515)	(83,765)
Contributions from noncontrolling interest	400	0
Other, net	5,135	4,552
Net cash used in financing activities	(22,509)	(6,445)
Net increase in cash and cash equivalents	7,051	3,744
Cash and cash equivalents at beginning of period	9,041	7,029
Cash and cash equivalents at end of period	16,092	10,773
Reportable Legal Entities | Genesis Energy Finance Corporation (Co-Issuer)
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	0	0
Payments to acquire fixed and intangible assets	0	0
Cash distributions received from equity investees - return of investment	0	0
Investments in equity investees		0
Acquisitions	0	0
Intercompany transfers	0	0
Repayments on loan to non-guarantor subsidiary	0	0
Contributions in aid of construction costs	0	0
Proceeds from asset sales	0	0
Other, net	0	0
Net cash used in investing activities	0	0
Borrowings on senior secured credit facility	0	0
Repayments on senior secured credit facility	0	0
Proceeds from issuance of senior unsecured notes	0
Repayments of Unsecured Debt	0
Proceeds from issuance of Class A convertible preferred units, net	0
Debt issuance costs	0	0
Intercompany transfers	0	0
Issuance of common units for cash, net	0	0
Distributions to partners/owners	0	0
Contributions from noncontrolling interest	0	0
Other, net	0	0
Net cash used in financing activities	0	0
Net increase in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	0	0
Reportable Legal Entities | Genesis Energy, L.P. (Parent and Co-Issuer)
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	18,637	42,623
Payments to acquire fixed and intangible assets	0	0
Cash distributions received from equity investees - return of investment	0	0
Investments in equity investees		(140,968)
Acquisitions	0	0
Intercompany transfers	9,407	109,342
Repayments on loan to non-guarantor subsidiary	0	0
Contributions in aid of construction costs	0	0
Proceeds from asset sales	0	0
Other, net	0	0
Net cash used in investing activities	9,407	(31,626)
Borrowings on senior secured credit facility	333,800	216,700
Repayments on senior secured credit facility	(154,000)	(284,900)
Proceeds from issuance of senior unsecured notes	0
Repayments of Unsecured Debt	145,170
Proceeds from issuance of Class A convertible preferred units, net	0
Debt issuance costs	(159)	0
Intercompany transfers	0	0
Issuance of common units for cash, net	0	140,968
Distributions to partners/owners	(62,515)	(83,765)
Contributions from noncontrolling interest	0	0
Other, net	0	0
Net cash used in financing activities	(28,044)	(10,997)
Net increase in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	6	6
Cash and cash equivalents at end of period	6	6
Reportable Legal Entities | Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	124,180	95,023
Payments to acquire fixed and intangible assets	(66,051)	(61,292)
Cash distributions received from equity investees - return of investment	9,277	9,083
Investments in equity investees		0
Acquisitions	0	0
Intercompany transfers	0	0
Repayments on loan to non-guarantor subsidiary	1,801	1,627
Contributions in aid of construction costs	0	124
Proceeds from asset sales	6	1,234
Other, net	0	0
Net cash used in investing activities	(54,967)	(49,224)
Borrowings on senior secured credit facility	0	0
Repayments on senior secured credit facility	0	0
Proceeds from issuance of senior unsecured notes	0
Repayments of Unsecured Debt	0
Proceeds from issuance of Class A convertible preferred units, net	0
Debt issuance costs	0	0
Intercompany transfers	(5,496)	(104,276)
Issuance of common units for cash, net	0	140,968
Distributions to partners/owners	(62,515)	(83,765)
Contributions from noncontrolling interest	0	0
Other, net	5,135	4,552
Net cash used in financing activities	(62,876)	(42,521)
Net increase in cash and cash equivalents	6,337	3,278
Cash and cash equivalents at beginning of period	8,340	6,360
Cash and cash equivalents at end of period	14,677	9,638
Reportable Legal Entities | Non-Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	874	2,007
Payments to acquire fixed and intangible assets	0	0
Cash distributions received from equity investees - return of investment	0	0
Investments in equity investees		0
Acquisitions	0	0
Intercompany transfers	0	0
Repayments on loan to non-guarantor subsidiary	0	0
Contributions in aid of construction costs	0	0
Proceeds from asset sales	0	0
Other, net	0	0
Net cash used in investing activities	0	0
Borrowings on senior secured credit facility	0	0
Repayments on senior secured credit facility	0	0
Proceeds from issuance of senior unsecured notes	0
Repayments of Unsecured Debt	0
Proceeds from issuance of Class A convertible preferred units, net	0
Debt issuance costs	0	0
Intercompany transfers	(3,911)	(5,066)
Issuance of common units for cash, net	0	0
Distributions to partners/owners	0	0
Contributions from noncontrolling interest	400	0
Other, net	3,351	3,525
Net cash used in financing activities	(160)	(1,541)
Net increase in cash and cash equivalents	714	466
Cash and cash equivalents at beginning of period	695	663
Cash and cash equivalents at end of period	1,409	1,129
Eliminations
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	(57,363)	(78,613)
Payments to acquire fixed and intangible assets	0	0
Cash distributions received from equity investees - return of investment	0	0
Investments in equity investees		140,968
Acquisitions	0	0
Intercompany transfers	(9,407)	(109,342)
Repayments on loan to non-guarantor subsidiary	(1,801)	(1,627)
Contributions in aid of construction costs	0	0
Proceeds from asset sales	0	0
Other, net	0	0
Net cash used in investing activities	(11,208)	29,999
Borrowings on senior secured credit facility	0	0
Repayments on senior secured credit facility	0	0
Proceeds from issuance of senior unsecured notes	0
Repayments of Unsecured Debt	0
Proceeds from issuance of Class A convertible preferred units, net	0
Debt issuance costs	0	0
Intercompany transfers	9,407	109,342
Issuance of common units for cash, net	0	(140,968)
Distributions to partners/owners	62,515	83,765
Contributions from noncontrolling interest	0	0
Other, net	(3,351)	(3,525)
Net cash used in financing activities	68,571	48,614
Net increase in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	$ 0	$ 0