Condensed Consolidated Balance Sheets (USD $) In Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2011	Dec. 31, 2010
Assets
Land	$ 44,620	$ 42,493
Buildings and improvements	436,602	420,704
Construction in progress	3,922
Real estate properties, gross	485,144	463,197
Less accumulated depreciation	(143,474)	(135,543)
Real estate properties, net	341,670	327,654
Mortgage notes receivable, net	79,328	75,465
Investment in preferred stock, at cost	38,132	38,132
Cash and cash equivalents	15,484	2,664
Marketable securities	9,510	22,476
Accounts receivable, net	473	471
Straight-line rent receivable	7,690	4,928
Assets held for sale, net	29,381	36,853
Deferred costs and other assets	629	698
Total Assets	522,297	509,341
Liabilities and Stockholders' Equity
Debt	48,125	37,765
Real estate purchase liability	4,000	4,000
Accounts payable and accrued expenses	3,915	3,388
Dividends payable	17,059	16,752
Deferred income	1,714	1,461
Earnest money deposit		3,475
Total Liabilities	74,813	66,841
Commitments and Contingencies
Stockholders' Equity
Common stock, $.01 par value; 40,000,000 shares authorized; 27,738,589 and 27,689,392 shares issued and outstanding, respectively	277	277
Capital in excess of par value	465,503	462,392
Cumulative dividends in excess of net income	(23,623)	(35,499)
Unrealized gains on marketable securities	5,327	15,330
Total Stockholders' Equity	447,484	442,500
Total Liabilities and Stockholders' Equity	$ 522,297	$ 509,341

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Represents the caption on the face of the balance sheet to indicate that the entity has entered into (1) purchase or supply arrangements that will require expending a portion of its resources to meet the terms thereof, and (2) is exposed to potential losses or, less frequently, gains, arising from (a) possible claims against a company's resources due to future performance under contract terms, and (b) possible losses or likely gains from uncertainties that will ultimately be resolved when one or more future events that are deemed likely to occur do occur or fail to occur. This caption alerts the reader that one or more notes to the financial statements disclose pertinent information about the entity's commitments and contingencies.

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Dollar value of issued common stock whether issued at par value, no par or stated value. This item includes treasury stock repurchased by the entity. Note: elements for number of common shares, par value and other disclosure concepts are in another section within stockholders' equity.

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Carrying amount at the balance sheet date of long-lived asset under construction that include construction costs to date on capital projects that have not been completed and assets being constructed that are not ready to be placed into service.

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The cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property, by the lessor or lessee, respectively. Such receivable should be reduced by allowances attributable to, for instance, credit risk associated with a lessee.

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Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.

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Total of all Liabilities and Stockholders' Equity items.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of loans from a bank with maturities initially due after one year or beyond the normal operating cycle if longer.

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The cumulative amount of depreciation for real estate property held for investment purposes.

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