Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Assets
Rental properties, net of accumulated depreciation of $661,029 and $635,535 at March 31, 2017 and December 31, 2016, respectively	$ 3,673,130	$ 3,595,762
Land held for development	22,530	22,530
Property under development	331,934	297,110
Mortgage notes and related accrued interest receivable	671,797	613,978
Investment in a direct financing lease, net	103,095	102,698
Investment in joint ventures	5,522	5,972
Cash and cash equivalents	14,446	19,335
Restricted cash	28,523	9,744
Accounts receivable, net	96,267	98,939
Other assets	99,538	98,954
Total assets	5,046,782	4,865,022
Liabilities:
Accounts payable and accrued liabilities	101,438	119,758
Common dividends payable	22,022	20,367
Preferred dividends payable	5,952	5,951
Unearned rents and interest	61,579	47,420
Debt	2,616,382	2,485,625
Total liabilities	2,807,373	2,679,121
Equity:
Common Shares, $.01 par value; 100,000,000 shares authorized; and 67,495,902 and 66,263,487 shares issued at March 31, 2017 and December 31, 2016, respectively	675	663
Preferred shares, $.01 par value; 25,000,000 shares authorized:
Additional paid-in-capital	2,755,108	2,677,046
Treasury shares at cost: 2,724,514 and 2,616,406 common shares at March 31, 2017 and December 31, 2016, respectively	(120,955)	(113,172)
Accumulated other comprehensive income	8,606	7,734
Distributions in excess of net income	(404,164)	(386,509)
Total equity	2,239,409	2,185,901
Total liabilities and equity	5,046,782	4,865,022
Series C Preferred Shares [Member]
Preferred shares, $.01 par value; 25,000,000 shares authorized:
Preferred shares	54	54
Series E Preferred Shares [Member]
Preferred shares, $.01 par value; 25,000,000 shares authorized:
Preferred shares	35	35
Series F Preferred Stock [Member]
Preferred shares, $.01 par value; 25,000,000 shares authorized:
Preferred shares	$ 50	$ 50