| Property Portfolio - Summary of the acquired lease intangible amortization (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
| Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018 | |
| In-place leases [Member] | ||||
| Property, Plant and Equipment [Line Items] | ||||
| Finite-Lived Intangible Assets, Accumulated Amortization | $ 1,033 | $ 647 | $ 2,562 | $ 1,797 | 
| Leasing Costs [Member] | ||||
| Property, Plant and Equipment [Line Items] | ||||
| Finite-Lived Intangible Assets, Accumulated Amortization | 467 | 307 | 1,195 | 848 | 
| Above Market Lease intangibles [Member] | ||||
| Property, Plant and Equipment [Line Items] | ||||
| Finite-Lived Intangible Assets, Accumulated Amortization | 343 | 240 | 895 | 620 | 
| Below Market Lease intangible [Member] | ||||
| Property, Plant and Equipment [Line Items] | ||||
| Finite-Lived Intangible Assets, Accumulated Amortization | $ 114 | $ 56 | $ 261 | $ 152 | 
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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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