Amount of environmental liabilities assumed at the acquisition date.

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The number of fuel sites owned or leased.

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Represents the number of owned, leased and supplied gasoline stations, either stand-alone or combined with a convenience store.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of assets acquired at the acquisition date.

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Amount of other liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Amount of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Business Combination - Current Year (Details) $ in Thousands		3 Months Ended
	Jul. 17, 2018 USD ($) location	Mar. 31, 2019 USD ($) item	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)
Acquisitions
Number of owned, leased and/or supplied gasoline stations \| item		1,578
Number of convenience stores \| item		296
Preliminary allocation of the purchase price
Goodwill		$ 326,486		$ 327,406
Amortization expense		2,976	$ 2,468
Champlain Oil Company [Member]
Acquisitions
Number of owned, leased and/or supplied gasoline stations \| location	37
Number of fuel sites owned or leased \| location	24
Number of gas stations under fuel supply agreements \| location	65
Purchase price including contingent consideration	$ 138,200
Preliminary allocation of the purchase price
Inventory	5,450
Prepaid expenses and other current assets	270
Property and equipment	112,871
Intangibles	12,936
Total identifiable assets purchased	131,527
Accrued expenses and other current liabilities	(131)
Environmental liabilities	(10,757)
Other non-current liabilities	(938)
Total liabilities assumed	(11,826)
Net identifiable assets acquired	119,701
Goodwill	18,478
Net assets acquired	138,179
Amortization expense		$ 600
Amount of goodwill deductible for tax purposes	$ 18,500
Champlain Oil Company [Member] \| Minimum
Preliminary allocation of the purchase price
Weighted average life	1 year
Champlain Oil Company [Member] \| Maximum
Preliminary allocation of the purchase price
Weighted average life	10 years