Summary of Significant Accounting Policies - Narrative - Operating Expenses (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Other operating expense reimbursement, percentage of average invested assets, threshold	2.00%
Other operating expense reimbursement, percentage of net income, threshold	25.00%
Due to affiliates	$ 4,985,918	$ 1,967,129
Advisor [Member]
Related Party Transaction [Line Items]
Due to affiliates	115,212
Advisor [Member] \| General and Administrative Expense [Member]
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party	$ 4,717,463

Other Operating Expense Reimbursement, Percentage of Average Invested Assets, Threshold

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Other Operating Expense Reimbursement, Percentage of Net Income, Threshold

+ References

No definition available.

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Carrying amount as of the balance sheet date of obligations due all related parties.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(3),(4))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.17)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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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.

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