v3.7.0.1
Credit Risk Concentrations - Additional Information (Detail) - customer
3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Dec. 31, 2016
Concentration Risk [Line Items]          
Number of tenants or common franchises 0   0    
Operating Expenses | Management Contracts Concentration Risk          
Concentration Risk [Line Items]          
Concentrations risk percentage 22.00% 32.00% 26.00% 25.00%  
Mortgages and Notes Payable | Credit Availability Concentration Risk | Financial Institution One          
Concentration Risk [Line Items]          
Concentrations risk percentage     28.00%   20.00%
Mortgages and Notes Payable | Credit Availability Concentration Risk | Financial Institution Two          
Concentration Risk [Line Items]          
Concentrations risk percentage     18.00%   18.00%
Mortgages and Notes Payable | Credit Availability Concentration Risk | Financial Institution Three          
Concentration Risk [Line Items]          
Concentrations risk percentage     14.00%   12.00%
Mortgages and Notes Payable | Credit Availability Concentration Risk | Financial Institution Four          
Concentration Risk [Line Items]          
Concentrations risk percentage     14.00%   11.00%