v3.8.0.1

Credit Risk Concentrations - Additional Information (Detail) - customer | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Concentration Risk [Line Items] |  |  |
Number of tenants or common franchises | 0 | 0 | 0
Operating Expenses | Management Contracts Concentration Risk |  |  |
Concentration Risk [Line Items] |  |  |
Concentrations risk percentage | 20.00% | 25.00% | 27.00%
Mortgages and Notes Payable | Credit Availability Concentration Risk | Financial Institution One |  |  |
Concentration Risk [Line Items] |  |  |
Concentrations risk percentage | 27.00% | 20.00% | 22.00%
Mortgages and Notes Payable | Credit Availability Concentration Risk | Financial Institution Two |  |  |
Concentration Risk [Line Items] |  |  |
Concentrations risk percentage | 17.00% | 18.00% | 13.00%
Mortgages and Notes Payable | Credit Availability Concentration Risk | Financial Institution Three |  |  |
Concentration Risk [Line Items] |  |  |
Concentrations risk percentage | 13.00% | 12.00% | 13.00%
Mortgages and Notes Payable | Credit Availability Concentration Risk | Financial Institution Four |  |  |
Concentration Risk [Line Items] |  |  |
Concentrations risk percentage | 11.00% | 11.00% | 11.00%
Mortgages and Notes Payable | Credit Availability Concentration Risk | Financial Institution Five |  |  |
Concentration Risk [Line Items] |  |  |
Concentrations risk percentage |  |  | 10.00%

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13531-108611 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6404-108592 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13537-108611 + Details
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