Quarterly report pursuant to Section 13 or 15(d)

STOCK-BASED COMPENSATION - Additional Information (Details)

v3.19.1
STOCK-BASED COMPENSATION - Additional Information (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 12 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Dec. 31, 2018
Jun. 30, 2012
Jul. 31, 2008
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Compensation expense $ 213 $ 592      
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    
Granted (in shares)     0    
Options, weighted average grant-date fair value (in dollars per share)     $ 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    
Granted (in shares) 0        
Exercised, intrinsic value $ 141 $ 616      
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)       1,500,000  
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