Income Taxes - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
	May 31, 2013	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Tax Credit Carryforward [Line Items]
Annual distribution of net taxable income for U.S. federal income tax not to apply to our earnings that we distribute (percent)		90.00%
Net taxable income subject to distribution (percent)		100.00%
Excise tax rate		4.00%
Income tax provision (benefit)		$ 323,000	$ (506,000)	$ 308,000
Deferred tax assets		0	0
Deferred tax liabilities		$ 0	$ 0
Common stock, shares issued	25,875,000	10,842,746	10,535,842	14,568,431
Net operating losses carried forward		$ 159,000,000.0
NOLs expiration date		Dec. 31, 2029
Open tax year		2016 2018 2019 2020
Internal Revenue Service [Member]
Tax Credit Carryforward [Line Items]
Net operating losses limit per annum		$ 2,000,000.0
Net operating losses limitations		the availability of our NOLs is generally limited to $2.0 million per annum