Partners' Capital, Mezzanine Capital and Distributions (Narrative) (Details)		3 Months Ended		6 Months Ended	31 Months Ended
	Mar. 06, 2025 $ / shares shares	Mar. 31, 2025 USD ($) $ / shares shares	Mar. 31, 2024 USD ($) $ / shares shares	Jun. 30, 2024 shares	Jun. 30, 2024	Dec. 31, 2024 shares	Aug. 08, 2023 shares
Partners Capital And Distributions [Line Items]
Common units outstanding (in units) | shares		122,464,318				122,464,318
Less: Accumulated distributions and returns attributable to Class A Convertible Preferred Units		$ (28,402,000)	$ (21,894,000)
Net loss attributable to common unitholders from continuing operations		(73,732,000)	(18,144,000)
Proceeds from Noncontrolling Interests		$ 7,767,000	$ 9,000,000
Net loss per common unit, diluted (in dollars per unit) | $ / shares		$ (4.06)	$ (0.09)
Net loss per common unit, basic (in dollars per unit) | $ / shares		$ (4.06)	$ (0.09)
Net Income (Loss) Available to Common Stockholders, Diluted		$ (497,477,000)	$ (10,541,000)
Net loss attributable to common unit holders		$ (497,477,000)	$ (10,541,000)
Weighted average outstanding units, basic (in units) | shares		122,464,000	122,464,000
Net income (loss) from discontinued operations		$ (423,745,000)	$ 7,603,000
Net income (loss) from continuing operations		(36,561,000)	11,353,000
Net income attributable to noncontrolling interests		$ (8,769,000)	$ (7,603,000)
Net loss from continuing operations per common unit, basic (in dollars per unit) | $ / shares		$ (0.60)	$ (0.15)
Net income (loss) from discontinued operations per common unit, diluted | $ / shares		(3.46)	0.06
Net income (loss) from discontinued operations per common unit, basic | $ / shares		(3.46)	0.06
Net loss from continuing operations per common unit, diluted (in dollars per unit) | $ / shares		$ (0.60)	$ (0.15)
Cameron Highway Oil Pipeline | Affiliated Entity
Partners Capital And Distributions [Line Items]
Percentage of ownership after transaction					64.00%
Independence Hub, LLC | Affiliated Entity | Genesis Energy, LLC
Partners Capital And Distributions [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent		80.00%
Class A Common Units | 2023 Repurchase Program
Partners Capital And Distributions [Line Items]
Percentage of shares authorized for repurchase							0.10
Shares authorized to be repurchased (in shares) | shares							12,253,922
Stock repurchased and cancelled (in shares) | shares				114,900
Class A Convertible Preferred Stock Units
Partners Capital And Distributions [Line Items]
Less: Accumulated distributions and returns attributable to Class A Convertible Preferred Units		$ (27,000,000.0)	$ (21,900,000)
Class A Convertible Preferred Units redeemed (in shares) | shares	7,416,196
Class A Convertible Preferred units redeemed (in dollars per share) | $ / shares	$ 35.40
Temporary equity, adjustment		$ 1,400,000
Limited Partner [Member] | Class A Common Units
Partners Capital And Distributions [Line Items]
Common units outstanding (in units) | shares		122,424,321
Limited Partner [Member] | Class B Common Units
Partners Capital And Distributions [Line Items]
Common units outstanding (in units) | shares		39,997
Limited Partner [Member] | Preferred Class A
Partners Capital And Distributions [Line Items]
Common units outstanding (in units) | shares		15,695,722