v3.26.1
ORGANIZATION (Details)
$ / shares in Units, $ in Thousands
 12 Months Ended 55 Months Ended 166 Months Ended
Oct. 03, 2014
USD ($)
shares
Dec. 31, 2025
property
shares
Dec. 31, 2023
USD ($)
shares
May 29, 2015
USD ($)
shares
Dec. 31, 2024
USD ($)
shares
Jan. 26, 2010
$ / shares
shares
Organizational Structure [Line Items]            
Common stock, shares issued (in shares)   148,516,246     148,516,246  
Private Placement            
Organizational Structure [Line Items]            
Issuance of common stock (in shares) 258,462          
Issuance of common stock, value | $ $ 2,400          
Office Building            
Organizational Structure [Line Items]            
Number of real estate properties | property   12        
Common Stock            
Organizational Structure [Line Items]            
Issuance of common stock (in shares)     1,900,374 169,006,162    
Issuance of common stock, value | $     $ 19 $ 1,700,000    
Shares of common stock sold under dividend reinvestment plan (in shares)         46,154,757  
Shares of common stock sold under dividend reinvestment plan, value | $         $ 471,300  
Redemptions of common stock (in shares)     1,349,082   74,644,349  
Redemptions of common stock, value | $     $ 14   $ 789,200  
KBS Capital Advisors LLC            
Organizational Structure [Line Items]            
Common stock, shares issued (in shares)           20,000
Common stock, purchase price per share (in dollars per share) | $ / shares           $ 10.00
KBS Capital Advisors LLC | Common Stock            
Organizational Structure [Line Items]            
Shares held by affiliate (in shares)   20,857        
Operating Partnership            
Organizational Structure [Line Items]            
Partnership interest in operating partnership   0.10%        
Partnership interest in the operating partnership and is its sole limited partner   99.90%