Segment Reporting (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Summarized financial information for the Partnership's reportable segments
Sales	$ 2,979,116us-gaap_SalesRevenueNet	$ 5,116,928us-gaap_SalesRevenueNet
Product margin	190,073glp_NetProductMargin	173,175glp_NetProductMargin
Gross profit	168,558us-gaap_GrossProfit	159,024us-gaap_GrossProfit
Wholesale Segment
Summarized financial information for the Partnership's reportable segments
Sales	1,971,946	3,998,556
Product margin	80,093	107,769
Gasoline sales: gasoline and gasoline blendstocks such as ethanol and naphtha
Summarized financial information for the Partnership's reportable segments
Sales	776,143	1,994,556
Product margin	29,829	49,663
Crude Oil
Summarized financial information for the Partnership's reportable segments
Sales	252,110	591,229
Product margin	15,257	23,490
Other oils and related products
Summarized financial information for the Partnership's reportable segments
Sales	943,693	1,412,771
Product margin	35,007	34,616
GDSO
Summarized financial information for the Partnership's reportable segments
Sales	780,409	802,876
Product margin	98,422	53,077
Gasoline
Summarized financial information for the Partnership's reportable segments
Sales	697,334	768,904
Product margin	61,699	33,280
Station operations
Summarized financial information for the Partnership's reportable segments
Sales	83,075	33,972
Product margin	36,723	19,797
Commercial Segment
Summarized financial information for the Partnership's reportable segments
Sales	226,761	315,496
Product margin	11,558	12,329
Operating costs and expenses not allocated to operating segments
Summarized financial information for the Partnership's reportable segments
Depreciation allocated to cost of sales	$ (21,515)	$ (14,151)

Represents the aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity as a result of non-GAAP financial measure.

No definition available.

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The expense recognized in the current period that allocates the cost of a tangible asset over the asset's useful life. This element applies only to an asset used in the production of goods sold.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.2(a))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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+ References

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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