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Real Estate and Intangible Assets - Business Combinations and Asset Acquisitions (Details) - USD ($) $ in Thousands | 9 Months Ended
--- | ---
Sep. 30, 2017 | Sep. 30, 2016
Business Acquisition [Line Items] |  |
Total Purchase Price | $ 94,421 | $ 40,900
Business Combinations |  |
Business Acquisition [Line Items] |  |
Total Purchase Price | 0 | 40,900
Business Combinations | Customer relationships |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 0 | 3,090
Business Combinations | Above market leases |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 0 | 0
Business Combinations | Below market leases |  |
Business Acquisition [Line Items] |  |
Liabilities assumed | 0 | 281
Business Combinations | Land |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 0 | 7,125
Business Combinations | Building and improvements |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 0 | 22,934
Business Combinations | Tenant Improvements |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 0 | 3,240
Business Combinations | In-place Leases |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 0 | 3,355
Business Combinations | Leasing Costs |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 0 | 1,437
Asset Acquisitions |  |
Business Acquisition [Line Items] |  |
Discount on Assumed Debt | 399 | 0
Total Purchase Price | 94,421 | 0
Asset Acquisitions | Interest rate swap |  |
Business Acquisition [Line Items] |  |
Liabilities assumed | 42 | 0
Asset Acquisitions | Customer relationships |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 6,851 | 0
Asset Acquisitions | Above market leases |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 1,916 | 0
Asset Acquisitions | Below market leases |  |
Business Acquisition [Line Items] |  |
Liabilities assumed | 1,769 | 0
Asset Acquisitions | Land |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 15,137 | 0
Asset Acquisitions | Building |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 51,186 | 0
Asset Acquisitions | Tenant Improvements |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 6,060 | 0
Asset Acquisitions | In-place Leases |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 9,516 | 0
Asset Acquisitions | Leasing Costs |  |
Business Acquisition [Line Items] |  |
Assets Acquired | $ 5,083 | $ 0

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