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Future Minimum Rents Narrative (Details) - tenants | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Future Minimum Rent [Line Items] |  |  |
Number Of Tenants Above Concentration Amount. | 0 | 0 | 0
Concentration Risk, Percentage | 10.00% | 10.00% | 10.00%
Maximum [Member] |  |  |
Future Minimum Rent [Line Items] |  |  |
Initial Term Lease Expiration Date | 2049 |  |

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