Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2018	Jan. 10, 2018
Accounting Policies [Abstract]
Percentage of taxable income not subject to federal corporate income tax to the extent it distributes if qualifies for taxation as a REIT	90.00%
Organization and offering expenses, term of reimbursement to Adviser	60 months
Organization and offering expenses incurred by Adviser and its affiliates on company's behalf	$ 3.7	$ 1.5

Percentage Of Net Taxable Income Distributed For Not Be Taxable Under Us Federal Income Taxes

No definition available.

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Period Type:	duration