Condensed Consolidating Financial Information (Condensed Consolidating Statement of Cash Flows) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	$ 150,816	$ 176,321
Payments to acquire fixed and intangible assets	(110,970)	(126,580)
Cash distributions received from equity investees - return of investment	17,828	17,956
Investments in equity investees	(395)	0
Acquisitions	0	(759)
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	1,192	38,237
Net cash used in investing activities	(92,345)	(71,022)
Borrowings on senior secured credit facility	543,100	410,700
Repayments on senior secured credit facility	(336,000)	(477,900)
Repayments of Unsecured Debt	145,170	0
Debt issuance costs	(224)	(7,536)
Intercompany transfers	0	0
Issuance of common units for cash, net	0	140,537
Distributions to partners/owners	(126,257)	(171,993)
Contributions from noncontrolling interest	1,320	725
Other, net	3,565	3,216
Net cash used in financing activities	(59,666)	(102,251)
Net increase (decrease) in cash and cash equivalents	(1,195)	3,048
Cash and cash equivalents at beginning of period	9,041	7,029
Cash and cash equivalents at end of period	7,846	10,077
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	0
Acquisitions		0
Intercompany transfers	0	0
Repayments on loan to non-guarantor subsidiary	0	0
Contributions in aid of construction costs		0
Proceeds from asset sales	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
Repayments of Unsecured Debt	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 (decrease) 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	9,724	102,991
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	(140,537)
Acquisitions		0
Intercompany transfers	54,827	143,738
Repayments on loan to non-guarantor subsidiary	0	0
Contributions in aid of construction costs		0
Proceeds from asset sales	0	0
Net cash used in investing activities	54,827	3,201
Borrowings on senior secured credit facility	543,100	410,700
Repayments on senior secured credit facility	(336,000)	(477,900)
Repayments of Unsecured Debt	145,170
Debt issuance costs	(224)	(7,536)
Intercompany transfers	0	0
Issuance of common units for cash, net	0	140,537
Distributions to partners/owners	(126,257)	(171,993)
Contributions from noncontrolling interest	0	0
Other, net	0	0
Net cash used in financing activities	(64,551)	(106,192)
Net increase (decrease) 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	255,552	234,371
Payments to acquire fixed and intangible assets	(110,970)	(126,580)
Cash distributions received from equity investees - return of investment	17,828	17,956
Investments in equity investees	(395)	0
Acquisitions		(759)
Intercompany transfers	0	0
Repayments on loan to non-guarantor subsidiary	3,647	3,296
Contributions in aid of construction costs		124
Proceeds from asset sales	1,192	38,237
Net cash used in investing activities	(88,698)	(67,726)
Borrowings on senior secured credit facility	0	0
Repayments on senior secured credit facility	0	0
Repayments of Unsecured Debt	0
Debt issuance costs	0	0
Intercompany transfers	(46,605)	(135,170)
Issuance of common units for cash, net	0	140,537
Distributions to partners/owners	(126,257)	(171,993)
Contributions from noncontrolling interest	0	0
Other, net	3,565	3,216
Net cash used in financing activities	(169,297)	(163,410)
Net increase (decrease) in cash and cash equivalents	(2,443)	3,235
Cash and cash equivalents at beginning of period	8,340	6,360
Cash and cash equivalents at end of period	5,897	9,595
Reportable Legal Entities | Non-Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	1,494	646
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	0
Acquisitions		0
Intercompany transfers	0	0
Repayments on loan to non-guarantor subsidiary	0	0
Contributions in aid of construction costs		0
Proceeds from asset sales	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
Repayments of Unsecured Debt	0
Debt issuance costs	0	0
Intercompany transfers	(8,222)	(8,568)
Issuance of common units for cash, net	0	0
Distributions to partners/owners	0	0
Contributions from noncontrolling interest	1,320	725
Other, net	6,656	7,010
Net cash used in financing activities	(246)	(833)
Net increase (decrease) in cash and cash equivalents	1,248	(187)
Cash and cash equivalents at beginning of period	695	663
Cash and cash equivalents at end of period	1,943	476
Eliminations
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	(115,954)	(161,687)
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	140,537
Acquisitions		0
Intercompany transfers	(54,827)	(143,738)
Repayments on loan to non-guarantor subsidiary	(3,647)	(3,296)
Contributions in aid of construction costs		0
Proceeds from asset sales	0	0
Net cash used in investing activities	(58,474)	(6,497)
Borrowings on senior secured credit facility	0	0
Repayments on senior secured credit facility	0	0
Repayments of Unsecured Debt	0
Debt issuance costs	0	0
Intercompany transfers	54,827	143,738
Issuance of common units for cash, net	0	(140,537)
Distributions to partners/owners	126,257	171,993
Contributions from noncontrolling interest	0	0
Other, net	(6,656)	(7,010)
Net cash used in financing activities	174,428	168,184
Net increase (decrease) 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