The annual rate paid for the use of letters of credit.

No definition available.

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- Definition

Line of credit facility, aggregate maximum borrowing capacity after accordion feature adjustment.

+ References

No definition available.

+ Details

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Namespace Prefix:	gel_
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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

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Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
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-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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Balance Type:	credit
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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+ Details

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Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Debt (Narrative) (Details) - USD ($)		3 Months Ended		9 Months Ended
Debt (Narrative) (Details) - USD ($)	Feb. 15, 2018	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Debt Instrument [Line Items]
Loss on extinguishment of debt	$ 3,300,000	$ 0	$ 0	$ 0	$ 3,339,000
Minimum
Debt Instrument [Line Items]
Letter of credit, fee percentage				1.50%
Maximum
Debt Instrument [Line Items]
Letter of credit, fee percentage				3.00%
Amended Facility \| Accordion Feature
Debt Instrument [Line Items]
Line of credit facility aggregate maximum borrowing capacity		2,000,000,000.0		$ 2,000,000,000.0
Senior Secured Credit Facility
Debt Instrument [Line Items]
Line of credit, unused capacity commitment fee percentage				0.50%
Credit facility, amount outstanding		947,000,000.0		$ 947,000,000.0
Total amount available for borrowings under credit facility		751,900,000		751,900,000
Senior Secured Credit Facility \| Petroleum Products
Debt Instrument [Line Items]
Credit facility, amount outstanding		12,600,000		$ 12,600,000
Senior Secured Credit Facility \| Minimum
Debt Instrument [Line Items]
Line of credit, unused capacity commitment fee percentage				0.25%
Senior Secured Credit Facility \| Maximum
Debt Instrument [Line Items]
Line of credit, unused capacity commitment fee percentage				0.50%
Senior Secured Credit Facility \| Letters Of Credit
Debt Instrument [Line Items]
Letter of credit, fee percentage				2.50%
Letters of credit, outstanding amount		1,100,000		$ 1,100,000
Senior Secured Credit Facility \| Letters Of Credit \| Maximum
Debt Instrument [Line Items]
Letters of credit, outstanding amount		100,000,000.0		100,000,000.0
Senior Secured Credit Facility \| Amended Facility
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity		1,700,000,000		1,700,000,000
Senior Secured Credit Facility \| Amended Facility \| Accordion Feature
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity		300,000,000.0		$ 300,000,000.0
Federal Funds Effective Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				0.50%
Federal Funds Effective Rate \| Maximum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				1.00%
LIBOR Rate \| Maximum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				1.00%
Eurodollar Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				2.50%
Eurodollar Rate \| Minimum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				1.50%
Eurodollar Rate \| Maximum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				3.00%
Alternate Base Rate \| Minimum
Debt Instrument [Line Items]
Letter of credit, fee percentage				0.50%
Alternate Base Rate \| Maximum
Debt Instrument [Line Items]
Letter of credit, fee percentage				2.00%
Applicable Margin
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				1.50%
6.250% senior unsecured notes
Debt Instrument [Line Items]
Debt issued		$ 450,000,000		$ 450,000,000		$ 450,000,000
Senior unsecured notes, stated rate		6.25%		6.25%		6.25%