Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	10 Months Ended	12 Months Ended	26 Months Ended
Sep. 13, 2017	Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Cash investment in money market fund		$ 599,000	$ 599,000	$ 0
Organization costs incurred	$ 243,000
Offering costs incurred			6,247,000
Percentage of distribution of annual REIT taxable income to stockholders to qualify as REIT		90.00%
Unrecognized interest or penalties			$ 0

Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant