Segment Reporting - Reconciliation (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
Reconciliation of the totals reported for the reportable segments to the applicable line items in the consolidated financial statements
Combined gross profit	$ 239,947		$ 167,143		$ 385,685	$ 323,987
Operating costs and 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)
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 tax (expense) benefit	(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
Unallocated
Operating costs and 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)
Long-lived asset impairment	1,724				1,724
Total costs and operating expenses	$ 139,357		$ 129,268		$ 266,288	$ 256,338