Summary of Significant Accounting Policies - Additional Information (Detail)		3 Months Ended		12 Months Ended
	Jul. 10, 2019 USD ($)	Mar. 31, 2021 USD ($) Property Segment	Mar. 31, 2020 USD ($) Property	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Summary of Significant Accounting Policies [Line Items]
Number of properties acquired | Property		0	0
Business acquisition, transaction costs		$ 0	$ 0
Days allowed for lease cancellation		30 days
Debt issuance costs		$ 1,606,390		$ 1,724,792
Offering cost as percentage of gross offering proceeds		1.00%
Maximum period for reimbursement of offering cost		60 days
Due to affiliates		$ 618,224	495,291
Gross proceeds from issuance of common stock			$ 3,313,677
Minimum percentage of ordinary taxable income to be distributed to stockholders		90.00%
Deferred tax asset, net operating loss		$ 2,800,000		2,400,000
Deferred tax liability, depreciation and other temporary book to tax differences		300,000		300,000
Deferred tax assets, net		$ 2,500,000		2,100,000
Number of reportable segments | Segment		2
Advisor [Member]
Summary of Significant Accounting Policies [Line Items]
Maximum period for reimbursement of offering expenses		60 days
Due to affiliates				600,000
Class Y and Z Common Stock [Member]
Summary of Significant Accounting Policies [Line Items]
Offering cost as percentage of gross offering proceeds		1.00%
Minimum offering cost rate		1.00%
Maximum offering cost rate		1.00%
Gross proceeds from issuance of common stock					$ 11,900,000
Class Y Common Stock [Member] | Primary Offering [Member]
Summary of Significant Accounting Policies [Line Items]
Gross proceeds from issuance of common stock	$ 250,000,000
Class Y Common Stock [Member] | Select Capital Corporation (Dealer Manager) [Member]
Summary of Significant Accounting Policies [Line Items]
Sale commission fees percentage of proceed from Primary Offering	3.00%	3.00%
Dealer manager fees percentage of proceed from sales in primary portion of offering	3.00%	3.00%
In-Place Leases [Member]
Summary of Significant Accounting Policies [Line Items]
Gross amount of lease intangibles		$ 22,300,000		22,300,000
Accumulated amortization of lease intangibles		$ 22,300,000		$ 21,700,000
Maximum [Member]
Summary of Significant Accounting Policies [Line Items]
Initial term of lease		12 months
Maximum [Member] | Advisor [Member]
Summary of Significant Accounting Policies [Line Items]
Percentage of organization and offering expenses funded by our advisor		1.00%
Maximum [Member] | Furniture, Fixtures and Equipment [Member]
Summary of Significant Accounting Policies [Line Items]
Standard depreciable life		7 years
Minimum [Member] | Class Y and Z Common Stock [Member]
Summary of Significant Accounting Policies [Line Items]
Percentage of organization and offering expenses funded by our advisor		1.00%
Minimum [Member] | Class Y and Z Common Stock [Member] | Advisor [Member]
Summary of Significant Accounting Policies [Line Items]
Percentage of organization and offering expenses expected at termination of public offering		1.00%
Percentage of receivable from advisor for organization and offering expenses incurred				1.00%
Minimum [Member] | Furniture, Fixtures and Equipment [Member]
Summary of Significant Accounting Policies [Line Items]
Standard depreciable life		3 years
Reno Student Housing, DST [Member]
Summary of Significant Accounting Policies [Line Items]
Beneficial interest for ownership percentage		2.60%
Power 5 Conference Student Housing [Member]
Summary of Significant Accounting Policies [Line Items]
Beneficial interest for ownership percentage		1.40%