Annual report pursuant to Section 13 and 15(d)

Related-Party Transactions - Additional Information (Detail)

v3.8.0.1
Related-Party Transactions - Additional Information (Detail) - USD ($)
 3 Months Ended 12 Months Ended
Apr. 01, 2017
Dec. 31, 2017
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Related Party Transaction [Line Items]          
Expected annual base management fee (as percent) 2.00%   2.00%    
Pre-incentive quarterly fee FFO in percentage of common stockholders equity that will reward the advisor (as percent) 1.75%   1.75%    
Pre-incentive annual fee FFO in percentage of common stockholders equity that will reward the advisor (as percent) 7.00%   7.00%    
Amount to be paid to Adviser in percentage of pre-incentive fee condition one (as percent) 100.00%   100.00%    
Pre-incentive fee in percentage of common stockholders equity that awards adviser hundred percent of amount of pre-incentive fee, maximum percentage (as percent) 2.1875%   2.1875%    
Maximum annual percentage of stockholders' equity to pay full pre-incentive fee to adviser (as percent) 8.75%   8.75%    
Amount to be paid to Adviser in percentage of pre-incentive fee condition two (as percent) 20.00%   20.00%    
Percentage of expected quarterly base management fee 0.50%        
Percentage of incentive fees on capital gains 15.00%        
Notice period for termination of agreement without cause 120 days        
Professional fees     $ 713,000    
Administration fees [1]     914,000 $ 771,000 $ 680,000
Taxable REIT Subsidiary          
Related Party Transaction [Line Items]          
Professional fees     71,000    
Administration fees     $ 22,000    
Minimum | Affiliated Entity          
Related Party Transaction [Line Items]          
Percentage of financing fee to amount of mortgage 0.50% 0.10%      
Maximum | Affiliated Entity          
Related Party Transaction [Line Items]          
Percentage of financing fee to amount of mortgage 1.00%        
[1] Refer to Note 6, “Related-Party Transactions,” for additional information.