v3.26.1
STOCK-BASED COMPENSATION PLANS - Stock-Based Compensation (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Stock-based compensation        
Stock-based compensation $ 4,829 $ 4,477 $ 10,786 $ 8,775
Location, Statement of Income, Balance [Axis]: us-gaap:GeneralAndAdministrativeExpense        
Stock-based compensation        
Stock-based compensation 3,052 2,725 7,198 4,773
Location, Statement of Income, Balance [Axis]: us-gaap:ResearchAndDevelopmentExpense        
Stock-based compensation        
Stock-based compensation 460 455 937 1,180
Location, Statement of Income, Balance [Axis]: us-gaap:SellingAndMarketingExpense        
Stock-based compensation        
Stock-based compensation 1,103 1,066 2,233 2,239
Location, Statement of Income, Balance [Axis]: rbbn:ProductCostOfSales        
Stock-based compensation        
Stock-based compensation 39 33 82 99
Location, Statement of Income, Balance [Axis]: rbbn:ServiceCostOfSales        
Stock-based compensation        
Stock-based compensation $ 175 $ 198 $ 336 $ 484