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CONSOLIDATED STATEMENTS OF CHANGES IN CAPITAL OF ERP OPERATING LIMITED PARTNERSHIP (Parenthetical) - Series K Preferred Stock [Member] | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Preferred Stock Preference Units Dividend Rate Percentage | 8.29% | 8.29% | 8.29%
Preferred Stock | ERPOP [Member] |  |  |
Preferred Stock Preference Units Dividend Rate Percentage | 8.29% | 8.29% | 8.29%

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- Definition The percentage rate used to calculate dividend payments on preferred shares/preference units. + References No definition available. + Details
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