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Revenue Recognition - Narrative (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2020 | Mar. 31, 2019
Disaggregation of Revenue [Line Items] |  |
Rental revenues | $ 54,110 | $ 56,778
Customer Concentration Risk | Revenue | Bloomberg |  |
Disaggregation of Revenue [Line Items] |  |
Rental revenues | $ 27,115 | $ 27,004
Percentage rent contributed by tenant | 50.00% | 48.00%

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