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Real Estate and Intangible Assets - Fair Value of Acquired Assets and Liabilities Assumed (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015
Business Acquisition [Line Items] |  |
Total Purchase Price on all Acquisitions | $ 66,570 | $ 77,798
Business Combinations [Member] |  |
Business Acquisition [Line Items] |  |
Total Purchase Price on all Acquisitions | 40,900 | 77,798
Asset Acquisitions [Member] |  |
Business Acquisition [Line Items] |  |
Total Purchase Price on all Acquisitions | 25,670 | 0
Customer Relationships [Member] | Business Combinations [Member] |  |
Business Acquisition [Line Items] |  |
Total Purchase Price | 3,090 | 5,408
Customer Relationships [Member] | Asset Acquisitions [Member] |  |
Business Acquisition [Line Items] |  |
Total Purchase Price | 1,406 | 0
Above Market Leases [Member] | Business Combinations [Member] |  |
Business Acquisition [Line Items] |  |
Total Purchase Price | 0 | 1,712
Above Market Leases [Member] | Asset Acquisitions [Member] |  |
Business Acquisition [Line Items] |  |
Total Purchase Price | 188 | 0
Below Market Leases [Member] | Business Combinations [Member] |  |
Business Acquisition [Line Items] |  |
Liabilities Assumed | (281) | (1,246)
Land [Member] | Business Combinations [Member] |  |
Business Acquisition [Line Items] |  |
Total Purchase Price | 7,125 | 10,528
Land [Member] | Asset Acquisitions [Member] |  |
Business Acquisition [Line Items] |  |
Total Purchase Price | 3,681 | 0
Building and Improvements [Member] | Business Combinations [Member] |  |
Business Acquisition [Line Items] |  |
Total Purchase Price | 22,934 | 42,652
Building and Improvements [Member] | Asset Acquisitions [Member] |  |
Business Acquisition [Line Items] |  |
Total Purchase Price | 11,682 | 0
Tenant Improvements [Member] | Business Combinations [Member] |  |
Business Acquisition [Line Items] |  |
Total Purchase Price | 3,240 | 6,996
Tenant Improvements [Member] | Asset Acquisitions [Member] |  |
Business Acquisition [Line Items] |  |
Total Purchase Price | 4,057 | 0
In-Place Leases [Member] | Business Combinations [Member] |  |
Business Acquisition [Line Items] |  |
Total Purchase Price | 3,355 | 7,410
In-Place Leases [Member] | Asset Acquisitions [Member] |  |
Business Acquisition [Line Items] |  |
Total Purchase Price | 2,669 | 0
Leasing Costs [Member] | Business Combinations [Member] |  |
Business Acquisition [Line Items] |  |
Total Purchase Price | 1,437 | 4,338
Leasing Costs [Member] | Asset Acquisitions [Member] |  |
Business Acquisition [Line Items] |  |
Total Purchase Price | $ 1,987 | $ 0

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- Definition The fair value of assets acquired in noncash investing or financing activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586 + Details
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