Consolidated Statements Of Cash Flows	12 Months Ended
	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
OPERATING ACTIVITIES
Net income	$ 4,358,000	$ 19,653,000	$ 8,764,000
Adjustments to reconcile net income to net cash provided by operating activities:
Gain on sales	(4,864,000)	(7,099,000)	(59,000)
Impairment charges	20,689,000	9,538,000	6,347,000
Early extinguishment of debt costs	4,829,000	210,000	2,623,000
Straight-line rents	(1,142,000)	(864,000)	(38,000)
Provision for doubtful accounts	2,273,000	1,715,000	1,198,000
Depreciation and amortization	40,053,000	40,115,000	40,787,000
Amortization of intangible lease liabilities, net	(4,361,000)	(2,518,000)	(2,751,000)
Expense relating to share-based compensation, net	3,763,000	3,552,000	2,930,000
Amortization of premium on mortgage loan payable	(80,000)	(130,000)	(236,000)
Amortization of deferred financing costs	1,224,000	1,325,000	1,524,000
Changes in operating assets and liabilities, net of effects of acquisitions and dispositions:
Rents and other receivables	(3,902,000)	(3,467,000)	(942,000)
Prepaid expenses and other	(6,591,000)	(4,600,000)	(1,829,000)
Accounts payable and accrued liabilities	1,651,000	(337,000)	929,000
Net cash provided by operating activities	57,900,000	57,093,000	59,247,000
INVESTING ACTIVITIES
Acquisitions of real estate	(179,000)	(32,442,000)	(31,923,000)
Expenditures for real estate improvements	(30,377,000)	(25,561,000)	(15,484,000)
Net proceeds from sales of real estate	19,118,000	12,506,000	96,170,000
Issuance of mortgage note receivable	(3,500,000)
Net cash (used in)/provided by investing activities	(14,938,000)	(45,497,000)	48,763,000
FINANCING ACTIVITIES
Repayments under revolving credit facility	(123,500,000)	(185,500,000)	(197,000,000)
Advances under revolving credit facility	168,500,000	168,500,000	191,000,000
Advance under term loan	75,000,000		100,000,000
Mortgage borrowing			50,000,000
Mortgage repayments	(80,330,000)	(10,294,000)	(218,403,000)
Payments of early extinguishment of debt costs	(5,159,000)		(2,487,000)
Payments of debt financing costs	(705,000)	(2,502,000)	(1,355,000)
Noncontrolling interests:
Distributions to limited partners	(90,000)	(70,000)	(71,000)
Redemption of OP Units	(7,000)	(24,000)	(8,000)
Net proceeds from sale of preferred stock		120,432,000
Redemptions of preferred stock	(50,016,000)	(112,510,000)
Common stock sales less issuance expenses, net	9,000	43,166,000	(142,000)
Common stock repurchases	(2,329,000)
Preferred stock dividends	(11,276,000)	(13,656,000)	(14,408,000)
Distributions to common shareholders	(18,301,000)	(17,681,000)	(17,049,000)
Net cash (used in) financing activities	(48,204,000)	(10,139,000)	(109,923,000)
Net (decrease)/increase in cash, cash equivalents and restricted cash	(5,242,000)	1,457,000	(1,913,000)
Cash, cash equivalents and restricted cash at beginning of year	7,219,000	5,762,000	7,675,000
Cash, cash equivalents and restricted cash at end of year	1,977,000	7,219,000	5,762,000
Reconciliation to consolidated balance sheets:
Cash and cash equivalents	1,977,000	3,702,000	2,882,000
Restricted cash		3,517,000	2,880,000
Cash, cash equivalents and restricted cash at end of year	$ 1,977,000	$ 7,219,000	$ 5,762,000