Unconsolidated Real Estate Joint Ventures (Unaudited Condensed Financial Information) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011	Dec. 31, 2011
Long-term debt	$ 1,224,840		$ 1,154,295
Note payable to EPR	0		0
Net income	21,390	41,733
Atlantic-EPR I [Member]
Rental properties, net	25,863	26,507
Cash	1,266	581
Long-term debt	14,852	0
Partners' equity	11,052	27,225
Rental revenue	678	1,130
Net income	(19)	407
Atlantic-EPR II [Member]
Rental properties, net	20,461	20,922
Cash	131	244
Long-term debt	12,126	12,505
Note payable to EPR	117	117
Partners' equity	8,075	8,180
Rental revenue	722	722
Net income	$ 367	$ 359

Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date. May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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The amount of ownership interest of different classes of partners in limited partnership.

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- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

+ References

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+ Details