Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)		12 Months Ended
	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Summary of Significant Accounting Policies [Line Items]
Percentage of real estate investment trust taxable income distributed for exemption of federal income tax		90.00%
Unrecognized tax benefits	$ 0	$ 0
Contingent payment			$ 900,000
ASU 2016-01
Summary of Significant Accounting Policies [Line Items]
Increase in net income attributable to available-for-sale securities		78,000
2017 Equity Incentive Plan
Summary of Significant Accounting Policies [Line Items]
Number of awards granted	0
Accounts Payable and Accrued Expenses
Summary of Significant Accounting Policies [Line Items]
Contingent payment	$ 900,000	$ 900,000	$ 900,000
Minimum
Summary of Significant Accounting Policies [Line Items]
Estimated useful lives of buildings and improvements		5 years
Maximum
Summary of Significant Accounting Policies [Line Items]
Estimated useful lives of buildings and improvements		39 years