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Real Estate and Intangible Assets - Business Combinations and Asset Acquisitions (Details) - USD ($) $ in Thousands | 9 Months Ended
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Sep. 30, 2021 | Sep. 30, 2020
Business Acquisition [Line Items] |  |
Total purchase price | $ 46,225 | $ 82,599
Land value subject to land lease agreement | 2,711 |
Loan receivable | 46 | 53
Prepaid rent | 62 |
Customer relationships |  |
Business Acquisition [Line Items] |  |
Assets acquired | 1,458 | 2,808
Above market leases |  |
Business Acquisition [Line Items] |  |
Assets acquired | 410 | 309
Below market leases |  |
Business Acquisition [Line Items] |  |
Liabilities assumed | (266) | (1,752)
Land |  |
Business Acquisition [Line Items] |  |
Assets acquired | 4,116 | 7,798
Building |  |
Business Acquisition [Line Items] |  |
Assets acquired | 33,113 | 61,930
Tenant Improvements |  |
Business Acquisition [Line Items] |  |
Assets acquired | 860 | 1,431
In-place leases |  |
Business Acquisition [Line Items] |  |
Assets acquired | 3,336 | 5,411
Leasing costs |  |
Business Acquisition [Line Items] |  |
Assets acquired | $ 3,198 | $ 4,664

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