Real Estate and Intangible Assets - Business Combinations and Asset Acquisitions (Details) - USD ($) $ in Thousands  | 
9 Months Ended | |
|---|---|---|
Sep. 30, 2020  | 
Sep. 30, 2019  | 
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| Business Acquisition [Line Items] | ||
| Total purchase price | $ 82,599 | $ 67,272 | 
| Land value subject to land lease agreement | 2,711 | |
| Loan receivable | 53 | |
| Prepaid rent | 62 | |
| Customer relationships | ||
| Business Acquisition [Line Items] | ||
| Assets acquired | 2,808 | 2,200 | 
| Above market leases | ||
| Business Acquisition [Line Items] | ||
| Assets acquired | 309 | 1,865 | 
| Below market leases | ||
| Business Acquisition [Line Items] | ||
| Liabilities assumed | (1,752) | (1,627) | 
| Land | ||
| Business Acquisition [Line Items] | ||
| Assets acquired | 7,798 | 5,046 | 
| Building and improvements | ||
| Business Acquisition [Line Items] | ||
| Assets acquired | 61,930 | 48,898 | 
| Tenant Improvements | ||
| Business Acquisition [Line Items] | ||
| Assets acquired | 1,431 | 1,541 | 
| In-place leases | ||
| Business Acquisition [Line Items] | ||
| Assets acquired | 5,411 | 4,868 | 
| Leasing costs | ||
| Business Acquisition [Line Items] | ||
| Assets acquired | $ 4,664 | $ 4,481 | 
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- Definition Land Subject to Land Lease Agreement, Fair Value No definition available. 
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- Definition Purchase price of acquired property. No definition available. 
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- Definition Amount at the balance sheet date that has been received by the entity that represents rents paid in advance. No definition available. 
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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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- Definition Amount of acquired direct financing lease receivable from business combination. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition The fair value of assets acquired in noncash investing or financing activities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition The fair value of liabilities assumed in noncash investing or financing activities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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