Summary of Significant Accounting Policies - Additional Information - Direct Financing Leases (Details)	12 Months Ended
Dec. 31, 2017 vessel
Direct financing lease
Property, Plant and Equipment [Line Items]
Number of vessels	1

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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