Asset Exchange Transactions With Circle K - Schedule of Acquisition of Properties in Closed Asset Exchange Transaction (Parenthetical) (Details) - Circle K Stores Inc. [Member] $ in Millions	Sep. 30, 2019 USD ($)
Business Acquisition [Line Items]
Note receivable from Circle K	$ 1.4
First Asset Exchange [Member]
Business Acquisition [Line Items]
Fair value of asset divested	0.2
Second Asset Exchange [Member]
Business Acquisition [Line Items]
Fair value of asset divested	$ 1.2

For an unclassified balance sheet, amounts due from parties associated with the reporting entity as evidenced by a written promise to pay.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.3)
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
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Balance Type:	debit
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