Fair Value - Schedule of Fair Value of Financial Assets and Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Financial assets:
Cash and cash equivalents	$ 31,177	$ 27,623
Restricted cash	1,322	1,047	$ 1,948	$ 1,662
Rent and other receivables	2,557	2,929
Financial liabilities:
Dividends payable	5,600	1,333
Accounts payable and accrued expenses	6,165	3,977
Term loan payable	50,000	50,000
Mortgage notes payable	365,090	365,377
Pension withdrawal liability	836	854
Estimate of Fair Value Measurement [Member]
Financial assets:
Cash and cash equivalents	31,177	27,623
Restricted cash	1,322	1,047
Rent and other receivables	2,557	2,929
Financial liabilities:
Dividends payable	5,600	1,333
Accounts payable and accrued expenses	6,165	3,977
Term loan payable	50,000	50,000
Pension withdrawal liability	857	911
Mortgages [Member]
Financial liabilities:
Mortgage notes payable	365,090	365,377
Mortgages [Member] | Estimate of Fair Value Measurement [Member]
Financial liabilities:
Mortgage notes payable	$ 359,136	$ 376,322