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Mortgage Note Receivable - Additional Information (Detail) | 3 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2017 USD ($) | Sep. 30, 2016 USD ($) | Sep. 30, 2017 USD ($) | Sep. 30, 2016 USD ($) | Jul. 31, 2015 | Apr. 14, 2015 USD ($) | Jul. 25, 2014 USD ($) ft²
Debt Disclosure [Abstract] |  |  |  |  |  |  |
Mortgage notes receivable | $ 0 |  | $ 0 |  |  |  | $ 5,600,000
Square Footage (unaudited) | ft² |  |  |  |  |  |  | 81,371
Interim financing loan |  |  |  |  |  | $ 300,000 |
Percentage of Interest earned in cash (as percent) |  |  |  |  | 9.00% |  |
Estimated internal rate of return (as percent) |  |  |  |  | 22.00% |  |
Interest income from mortgage note receivable | $ 0 | $ 0 | $ 0 | $ 385,000 |  |  |

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- Definition Effect of Mortgage Loan Rate of Return Estimate + References No definition available. + Details
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- Definition Interest income from mortgage note receivable. + References No definition available. + Details
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- Definition Interim financing loan for acquisition. + References No definition available. + Details
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- Definition Percentage of Mortgage Loan Interest Earned in Cash + References No definition available. + Details
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- References No definition available. + Details
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- Definition Total carrying amount of mortgage loans as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 10 -Section S99 -Paragraph 6 -Subparagraph (SX 210.5-04.(c) Schedule IV) -URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 948 -SubTopic 310 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-29.6) -URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014 + Details
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