Stockholders' Equity - Additional Information (Detail) - USD ($)					12 Months Ended
	Dec. 03, 2021	Aug. 11, 2021	Nov. 08, 2016	Jun. 09, 2011	Dec. 31, 2021	Dec. 31, 2020
Stockholders' Equity Note [Line Items]
Shares of preferred stock authorized					10,000,000	10,000,000
Par value per share (in dollars per share)					$ 0.0001	$ 0.0001
Shares of common stock authorized for issuance					100,000,000	100,000,000
Common stock, par value (in dollars per share)					$ 0.0001	$ 0.0001
Shares of common stock issued					13,333,335	13,627,220
Shares of common stock outstanding					13,333,335	13,627,220
Repurchases - common stock					$ 6,279,000
Percentage of taxable income which should be distributed to be qualified as REIT					90.00%
Options expiration period					10 years
Stock compensation expense					$ 1,080,000	$ 784,000
Common stock value per share					$ 18.15
Unamortized stock compensation					$ 1,851,000
Outstanding at the end of the period (in shares)					816,461
Vested (in shares)					662,331
Stock Options [Member]
Stockholders' Equity Note [Line Items]
Stock options outstanding					200,000
Stock options exercisable					200,000
Restricted Stock [Member]
Stockholders' Equity Note [Line Items]
Weighted average period for recognition					2 years 4 months 24 days
Vested (in shares)					90,278
Non-employee Directors and Key Officers [Member]
Stockholders' Equity Note [Line Items]
Stock compensation expense					$ 0	$ 0
2007 Incentive Award Plan [Member]
Stockholders' Equity Note [Line Items]
Number of shares of common stock which may be awarded					1,000,000
Share-based compensation award plan , expiration date					Jun. 11, 2017
2007 Incentive Award Plan [Member] | Non-employee Directors [Member]
Stockholders' Equity Note [Line Items]
Stock options granted				10,000
2007 Incentive Award Plan [Member] | Key Officers [Member] | Non-qualified Stock Options [Member]
Stockholders' Equity Note [Line Items]
Stock options granted			200,000
Vesting period			3 years
Stock options granted exercise price			$ 10.40
2017 Incentive Award Plan [Member]
Stockholders' Equity Note [Line Items]
Number of shares of common stock which may be awarded					2,000,000
Plan effective date					Apr. 24, 2017
Number of shares available for future issuance					1,626,326
Federal Income Taxes [Member]
Stockholders' Equity Note [Line Items]
Percentage of taxable income which should be distributed in order not to be subject to corporate federal income taxes on retained income					100.00%
Share Redemption Program [Member]
Stockholders' Equity Note [Line Items]
Number of shares purchased	63,411
Share price	$ 15.77
Repurchases - common stock	$ 1,000,000.0
Self-Tender Offer [Member]
Stockholders' Equity Note [Line Items]
Number of shares purchased		377,107
Share price		$ 14.00
Repurchases - common stock		$ 5,300,000
Series A Preferred Stock [Member]
Stockholders' Equity Note [Line Items]
Shares of preferred stock authorized					500,000	500,000
Par value per share (in dollars per share)					$ 0.0001	$ 0.0001
Preferred stock, shares outstanding					0	0
Series B Preferred Stock, Non-Voting [Member]
Stockholders' Equity Note [Line Items]
Shares of preferred stock authorized					6,500,000	6,500,000
Par value per share (in dollars per share)					$ 0.0001	$ 0.0001
Preferred stock, voting rights					There are no voting rights associated with the Series B preferred stock.
Preferred stock, shares outstanding					0	0