Annual report pursuant to Section 13 and 15(d)

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)

v2.4.1.9
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) (USD $)
 12 Months Ended 1 Months Ended
Dec. 31, 2014
item
Dec. 31, 2013
Dec. 31, 2012
Feb. 28, 2014
Stock Based Compensation        
Number of stock option plans 3rigl_ShareBasedCompensationNumberOfStockOptionPlans      
Stock compensation expense $ 9,787,000us-gaap_ShareBasedCompensation $ 7,166,000us-gaap_ShareBasedCompensation $ 12,617,000us-gaap_ShareBasedCompensation  
Performance Shares [Member]        
Stock Based Compensation        
Granted (in shares) 950,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross
/ us-gaap_AwardTypeAxis
= us-gaap_PerformanceSharesMember 		    950,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross
/ us-gaap_AwardTypeAxis
= us-gaap_PerformanceSharesMember
Fair value of shares granted       2,500,000rigl_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantInPeriodFairValue
/ us-gaap_AwardTypeAxis
= us-gaap_PerformanceSharesMember
Stock compensation expense $ 453,000us-gaap_ShareBasedCompensation
/ us-gaap_AwardTypeAxis
= us-gaap_PerformanceSharesMember 		     
Employee Stock [Member]        
Stock Based Compensation        
Purchase price of common shares as a percentage of the fair market value on the first day of the offering period 85.00%rigl_ShareBasedCompensationArrangementByShareBasedPaymentAwardPurchasePriceOfCommonStockPercentageOnFirstDayOfOfferingPeriod
/ us-gaap_PlanNameAxis
= us-gaap_EmployeeStockMember 		     
Purchase price of common shares as a percentage of the fair market value on the purchase date 85.00%us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent
/ us-gaap_PlanNameAxis
= us-gaap_EmployeeStockMember