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Real Estate and Intangible Assets - Business Combinations and Asset Acquisitions (Details) - USD ($) $ in Thousands | 6 Months Ended
--- | ---
Jun. 30, 2017 | Jun. 30, 2016
Business Acquisition [Line Items] |  |
Total Purchase Price | $ 15,697 | $ 17,000
Business Combinations |  |
Business Acquisition [Line Items] |  |
Total Purchase Price | 0 | 17,000
Business Combinations | Customer relationships |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 0 | 1,675
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 | 30
Business Combinations | Land |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 0 | 3,008
Business Combinations | Building and improvements |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 0 | 8,973
Business Combinations | Tenant Improvements |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 0 | 1,685
Business Combinations | In-place Leases |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 0 | 1,352
Business Combinations | Leasing Costs |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 0 | 337
Asset Acquisitions |  |
Business Acquisition [Line Items] |  |
Discount on Assumed Debt | 399 | 0
Total Purchase Price | 15,697 | 0
Asset Acquisitions | Interest rate swap |  |
Business Acquisition [Line Items] |  |
Liabilities assumed | 42 | 0
Asset Acquisitions | Customer relationships |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 1,256 | 0
Asset Acquisitions | Below market leases |  |
Business Acquisition [Line Items] |  |
Liabilities assumed | 1,030 | 0
Asset Acquisitions | Land |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 1,996 | 0
Asset Acquisitions | Building |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 9,975 | 0
Asset Acquisitions | Tenant Improvements |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 905 | 0
Asset Acquisitions | In-place Leases |  |
Business Acquisition [Line Items] |  |
Assets Acquired | 1,690 | 0
Asset Acquisitions | Leasing Costs |  |
Business Acquisition [Line Items] |  |
Assets Acquired | $ 464 | $ 0

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