Quarterly report pursuant to Section 13 or 15(d)

STOCK-BASED COMPENSATION - Additional Information (Details)

v3.19.3
STOCK-BASED COMPENSATION - Additional Information (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2019
Sep. 30, 2018
Sep. 30, 2019
Sep. 30, 2018
Jun. 30, 2012
Jul. 31, 2008
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Compensation expense $ 300 $ 600 $ 904 $ 1,002    
Stock Option Plan for Key Employees            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Shares authorized (in shares)           1,000,000
Stock Option Plan for Key Employees | Stock Options            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Stock-based compensation, term of award     10 years      
Options, weighted average grant-date fair value (in dollars per share) $ 0 $ 0        
Shares issued during period (in shares)     11,000      
Stock Option Plan for Key Employees | Stock Options and Warrants            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Awards granted during period (in shares)   0 0 0    
Options granted (in shares) 0 0 0      
Exercised, intrinsic value     $ 100 $ 600    
Awards exercised (in shares)     85,000      
Trecora Resources Stock and Incentive Plan            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Shares authorized (in shares)         2,500,000  
Minimum | Stock Option Plan for Key Employees | Stock Options            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Vesting period     4 years      
Minimum | Trecora Resources Stock and Incentive Plan | Restricted Stock Unit Awards            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Vesting period     2 years 6 months      
Maximum | Stock Option Plan for Key Employees | Stock Options            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Vesting period     5 years      
Maximum | Trecora Resources Stock and Incentive Plan | Restricted Stock Unit Awards            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Vesting period     5 years      
COMMON STOCK | Stock Option Plan for Key Employees | Stock Options            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Options outstanding, in-the-money (in shares) 100,000   100,000