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Mortgage Note Receivable - Additional Information (Detail) | 12 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) | Jul. 31, 2015 | Jun. 30, 2015 | Apr. 14, 2015 USD ($) | Dec. 31, 2014 USD ($) | Jul. 25, 2014 USD ($) ft²
Debt Disclosure [Abstract] |  |  |  |  |  |  |  |
Second mortgage development loan | $ 0 | $ 0 | $ 5,900,000 |  |  |  | $ 5,600,000 | $ 5,600,000
Property area | ft² |  |  |  |  |  |  |  | 81,371
Interim financing loan |  |  |  |  |  | $ 300,000 |  |
Percentage of Interest earned in cash (as percent) |  |  |  | 9.00% |  |  |  |
Estimated percentage of rate of Interest (as percent) |  |  |  |  | 22.00% |  |  |
Cash interest income and accrued exit fee revenue recognized | 0 | $ 385,000 | $ 1,121,000 |  |  |  |  |
Mortgage notes receivable | $ 0 |  |  |  |  |  |  |

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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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- Definition Area of a real estate property. + 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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- Definition Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.3) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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