Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
OPERATING ACTIVITIES
Net (loss) income	$ (45,003,000)	$ (520,000)	$ 1,566,000
Adjustments to reconcile net loss to net cash provided by operating activities:
Gain on sales	(49,904,000)	(4,396,000)	(2,942,000)
Impairment charges	99,888,000	7,607,000	8,938,000
Straight-line rents and expenses, net	(161,000)	1,279,000	(265,000)
Provision for doubtful accounts	1,114,000	1,478,000	412,000
Depreciation and amortization	39,454,000	48,412,000	45,861,000
Amortization of intangible lease liabilities, net	(1,074,000)	(1,373,000)	(2,827,000)
Expense relating to share-based compensation, net	3,043,000	3,723,000	4,117,000
Amortization of deferred financing costs	1,360,000	1,331,000	1,286,000
Changes in operating assets and liabilities, net of effects of acquisitions and dispositions:
Rents and other receivables	(1,266,000)	(2,811,000)	(812,000)
Prepaid expenses and other	(2,709,000)	(9,216,000)	(3,037,000)
Accounts payable and accrued liabilities	220,000	(2,934,000)	1,378,000
Net cash provided by operating activities	44,962,000	42,580,000	53,675,000
INVESTING ACTIVITIES
Expenditures for real estate improvements	(28,309,000)	(39,551,000)	(31,910,000)
Net proceeds from sales of real estate	104,497,000	21,182,000	18,651,000
Contributions to unconsolidated joint venture	(4,654,000)
Acquisition of real estate			(9,083,000)
Net cash provided by (used in) investing activities	71,534,000	(18,369,000)	(22,342,000)
FINANCING ACTIVITIES
Repayments under revolving credit facility	(188,000,000)	(104,000,000)	(21,000,000)
Advances under revolving credit facility	79,000,000	173,000,000	27,000,000
Repayment under term loan	(100,000,000)	(75,000,000)
Termination payment related to interest rate swap	(503,000)
Mortgage proceeds	114,000,000
Mortgage repayments	(1,110,000)	(1,067,000)	(1,027,000)
Payments of debt financing costs	(3,278,000)	(326,000)
Noncontrolling interests:
Purchase of minority interest	(276,000)
Distributions to limited partners	(20,000)	(42,000)	(111,000)
Redemption of OP units	(8,000)		(43,000)
Common stock sales less issuance expenses, net		13,000	22,000
Common stock repurchases			(6,844,000)
Preferred stock dividends	(10,752,000)	(10,752,000)	(10,752,000)
Distributions to common shareholders	(3,917,000)	(7,147,000)	(17,808,000)
Net cash used in financing activities	(114,864,000)	(25,321,000)	(30,563,000)
Net increase (decrease) in cash, cash equivalents and restricted cash	1,632,000	(1,110,000)	770,000
Cash, cash equivalents and restricted cash at beginning of period	1,637,000	2,747,000	1,977,000
Cash, cash equivalents and restricted cash at end of period	3,269,000	1,637,000	2,747,000
Reconciliation to consolidated balance sheets:
Cash and cash equivalents	3,039,000	1,637,000	2,747,000
Restricted cash	230,000
Cash, cash equivalents and restricted cash at end of period	$ 3,269,000	$ 1,637,000	$ 2,747,000