Supp Guarantor Cond Cons Fin Stmts - I/S (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019
Condensed Income Statements, Captions [Line Items]
Sales	$ 1,469,577		$ 3,507,540		$ 4,064,670	$ 6,487,166
Cost of sales	1,229,630		3,340,397		3,678,985	6,163,179
Gross profit	239,947		167,143		385,685	323,987
Costs and operating expenses:
Selling, general and administrative expenses	59,017		40,968		99,940	82,058
Operating expenses	76,714		86,451		159,267	169,395
Lease exit and termination gain						(493)
Amortization expense	2,713		2,977		5,425	5,953
Net gain on sale and disposition of assets	(811)		(1,128)		(68)	(575)
Goodwill and long-lived asset impairment	1,724				1,724
Total costs and operating expenses	139,357		129,268		266,288	256,338
Operating income	100,590		37,875		119,397	67,649
Interest expense	(21,089)		(23,066)		(42,690)	(46,022)
Income before income tax (expense) benefit	79,501		14,809		76,707	21,627
Income tax benefit (expense)	(3,528)		(438)		2,341	(462)
Net income	75,973	$ 3,075	14,371	$ 6,794	79,048	21,165
Net loss attributable to noncontrolling interest	289		118		490	450
Net income attributable to Global Partners LP	76,262		14,489		79,538	21,615
Less: General partner's interest in net income, including incentive distribution rights	511		366		533	670
Reportable Legal Entities [Member] | (Issuer) Guarantor Subsidiaries
Condensed Income Statements, Captions [Line Items]
Sales	1,469,017		3,507,137		4,063,825	6,486,499
Cost of sales	1,229,572		3,340,184		3,678,689	6,162,384
Gross profit	239,445		166,953		385,136	324,115
Costs and operating expenses:
Selling, general and administrative expenses	58,182		40,867		99,006	81,859
Operating expenses	76,323		86,068		158,426	168,597
Lease exit and termination gain						(493)
Amortization expense	2,713		2,977		5,425	5,953
Net gain on sale and disposition of assets	(811)		(1,128)		(68)	(575)
Goodwill and long-lived asset impairment	1,724				1,724
Total costs and operating expenses	138,131		128,784		264,513	255,341
Operating income	101,314		38,169		120,623	68,774
Interest expense	(21,089)		(23,066)		(42,690)	(46,022)
Income before income tax (expense) benefit	80,225		15,103		77,933	22,752
Income tax benefit (expense)	(3,528)		(438)		2,341	(462)
Net income	76,697		14,665		80,274	22,290
Net income attributable to Global Partners LP	76,697		14,665		80,274	22,290
Less: General partner's interest in net income, including incentive distribution rights	511		366		533	670
Reportable Legal Entities [Member] | Non-Guarantor Subsidiary
Condensed Income Statements, Captions [Line Items]
Sales	780		526		1,111	885
Cost of sales	278		336		562	1,013
Gross profit	502		190		549	(128)
Costs and operating expenses:
Selling, general and administrative expenses	835		101		934	199
Operating expenses	391		383		841	798
Total costs and operating expenses	1,226		484		1,775	997
Operating income	(724)		(294)		(1,226)	(1,125)
Income before income tax (expense) benefit	(724)		(294)		(1,226)	(1,125)
Net income	(724)		(294)		(1,226)	(1,125)
Net loss attributable to noncontrolling interest	289		118		490	450
Net income attributable to Global Partners LP	(435)		(176)		(736)	(675)
Eliminations
Condensed Income Statements, Captions [Line Items]
Sales	(220)		(123)		(266)	(218)
Cost of sales	(220)		(123)		(266)	(218)
Series A Preferred Limited Partners
Costs and operating expenses:
Limited partners' interest in net income	1,682		1,682		3,364	3,364
Series A Preferred Limited Partners | Reportable Legal Entities [Member] | (Issuer) Guarantor Subsidiaries
Costs and operating expenses:
Limited partners' interest in net income	1,682		1,682		3,364	3,364
Common Limited Partners
Costs and operating expenses:
Limited partners' interest in net income	74,069		12,441		75,641	17,581
Common Limited Partners | Reportable Legal Entities [Member] | (Issuer) Guarantor Subsidiaries
Costs and operating expenses:
Limited partners' interest in net income	74,504		12,617		76,377	18,256
Common Limited Partners | Reportable Legal Entities [Member] | Non-Guarantor Subsidiary
Costs and operating expenses:
Limited partners' interest in net income	$ (435)		$ (176)		$ (736)	$ (675)