Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Cash flows from operating activities:
Net income	$ 63,018	$ 52,466
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	8,768	8,322
Straight-line rent adjustment	(2,762)	(2,286)
Non-cash interest income on construction loan	(781)	(137)
Provision for loan and realty recoveries	(99)	(573)
Gain on sale of real estate	(3,348)	(2,004)
Net realized gains on sales of marketable securities	(9,899)	(2)
Share-based compensation	2,912	2,204
Change in fair value of interest rate swap agreement	922	0
Changes in operating assets and liabilities:
Accounts receivable	(2)	96
Deferred costs and other assets	69	(364)
Accounts payable and accrued expenses	(395)	81
Deferred income	253	561
Net cash provided by operating activities	58,656	58,364
Cash flows from investing activities:
Investment in mortgage notes receivable	(6,567)	(9,988)
Collection of mortgage notes receivable	3,584	8,616
Investment in real estate properties	24,935	88,478
Receipt of earnest money deposit	525	3,250
Proceeds from disposition of real estate properties	8,971	6,247
Proceeds from sales of marketable securities	12,862	70
Net cash (used in) investing activities	(5,560)	(80,283)
Cash flows from financing activities:
Net change in borrowings under a revolving credit facility	(37,765)	28,234
Borrowings on term loan	50,000	0
Principal payments on term loan	(1,875)	0
Stock options exercised	199	184
Dividends paid to stockholders	(50,835)	(49,766)
Net cash (used in) financing activities	(40,276)	(21,348)
Increase (decrease) in cash and cash equivalents	12,820	(43,267)
Cash and cash equivalents, beginning of period	2,664	45,718
Cash and cash equivalents, end of period	15,484	2,451
Supplemental disclosure of cash flow information:
Interest paid	1,414	581
Supplemental schedule of non-cash activities:
Settlement of mortgage note by real estate acquisition (Note 8)	0	22,936
Cash withheld at closing of real estate acquisition (Note 8)	0	1,000
Earnest money deposit applied to sale of real estate	$ 4,000	$ 0

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