Related-Party Transactions - Additional Information (Details)			3 Months Ended			11 Months Ended
	Jan. 15, 2020	Apr. 01, 2019 USD ($) gal	Mar. 31, 2020 USD ($) Site	Mar. 25, 2020 USD ($)	Mar. 31, 2019 USD ($)	Nov. 18, 2019 Store	Jan. 31, 2020 Store	Jan. 01, 2020 gal	Dec. 31, 2019 USD ($)
Related Party Transaction [Line Items]
Accounts receivable from related parties			$ 1,687,000						$ 4,299,000
Rental income			22,688,000		$ 21,638,000
Accounts payable to related parties			999,000						431,000
Incentive distribution			133,000		133,000
Cost of services			355,966,000		434,709,000
Accounts receivable from related parties			1,687,000						4,299,000
Income from CST Fuel Supply equity interests			3,202,000		3,426,000
Topper Group Omnibus Agreement [Member]
Related Party Transaction [Line Items]
Partnership agreement effective date	Jan. 01, 2020
Cost and expenses incurred			$ 3,500,000
Wholesale Fuel Supply Contracts/Rights [Member] | CST Brands Inc. [Member]
Related Party Transaction [Line Items]
Equity method investment, ownership percentage			17.50%
Income from CST Fuel Supply equity interests			$ 3,200,000		3,400,000
Transitional Omnibus Agreement [Member]
Related Party Transaction [Line Items]
Accounts payable to related parties, noncurrent			3,500						4,600
Transitional Omnibus Agreement [Member] | CST Fuel Supply Exchange [Member]
Related Party Transaction [Line Items]
Reduction of operating expenses				$ 500,000
DMS [Member]
Related Party Transaction [Line Items]
Accounts receivable from related parties			$ 1,100,000						4,100,000
Decrease in rental income		$ 500,000
Fuel purchase agreement reduced per gallon | gal		0.01
Additional fuel purchase agreement reduced per gallon | gal								0.005
Number of remaining fuel deliveries covered by fuel supply agreement | Site			85
Number of Stores | Store							12
Accounts receivable from related parties			$ 1,100,000						4,100,000
TopStar [Member]
Related Party Transaction [Line Items]
Rental income			100,000
Rent expense			300,000		300,000
Accounts payable to related parties			200,000						100,000
Cost of services			100,000		400,000
Topper Group [Member]
Related Party Transaction [Line Items]
Incentive distribution			100,000
Dividends cash			7,900,000
Topper Group [Member] | Topper Group Omnibus Agreement [Member]
Related Party Transaction [Line Items]
Right of termination prior written notice period	180 days
Accounts payable to related parties			600,000
The General Partner [Member] | Topper Group Omnibus Agreement [Member]
Related Party Transaction [Line Items]
Right of termination prior written notice period	60 days
CST Brands Inc. [Member]
Related Party Transaction [Line Items]
Rent expense			200,000		200,000
Circle K Stores Inc. [Member]
Related Party Transaction [Line Items]
Number of Stores | Store						46
Incentive distribution					100,000
Dividends cash					3,900,000
Number of retail sites leased to related party | Store						40
Lessor leasing arrangements, operating leases, initial term						10 years
Amounts payable to fuel purchases and freight commissions to related parties			2,000,000						4,700,000
Circle K Stores Inc. [Member] | Franchise [Member]
Related Party Transaction [Line Items]
Cost of services					400,000
Circle K Stores Inc. [Member] | Fuel Sales Transaction [Member]
Related Party Transaction [Line Items]
Accounts receivable from related parties			1,100,000						3,100,000
Accounts receivable from related parties			1,100,000						3,100,000
Circle K Stores Inc. [Member] | Jet-Pep Assets Acquisition [Member]
Related Party Transaction [Line Items]
Purchases from related party			36,800,000		37,400,000
Circle K Stores Inc. [Member] | Transitional Omnibus Agreement and Circle K Omnibus Agreement [Member]
Related Party Transaction [Line Items]
Cost and expenses incurred					2,900,000
Circle K Stores Inc. [Member] | Transitional Omnibus Agreement [Member]
Related Party Transaction [Line Items]
Accounts payable to related parties			$ 8,600,000						$ 11,500,000
Couche-Tard [Member]
Related Party Transaction [Line Items]
Commission on transportation costs					$ 200,000