Quarterly report pursuant to Section 13 or 15(d)

STOCK-BASED COMPENSATION (Details Textual)

v2.4.1.9
STOCK-BASED COMPENSATION (Details Textual) (USD $)
 3 Months Ended
Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross 141,805us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross
Employee Service Share Based Compensation Nonvested Total Compensation In Current Year $ 620,000clrb_EmployeeServiceShareBasedCompensationNonvestedTotalCompensationInCurrentYear
Employee Service Share Based Compensation Nonvested Total Compensation In Year Two 476,000clrb_EmployeeServiceShareBasedCompensationNonvestedTotalCompensationInYearTwo
Employee Service Share Based Compensation Nonvested Total Compensation In Year Three 290,000clrb_EmployeeServiceShareBasedCompensationNonvestedTotalCompensationInYearThree
Weighted-Average Grant-Date Fair Value Of Vested Options Outstanding (in dollars per share) $ 13.65us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedWeightedAverageGrantDateFairValue
Weighted Average Grant Date Fair Value Of Unvested Options Outstanding (in dollars per share) $ 4.35us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValue
Share Based Compensation Arrangement By Share Based Payment Award Options Unvested and Expected To Vest Outstanding Number (in shares) 381,996clrb_ShareBasedCompensationArrangementBySharebasedPaymentAwardOptionsUnvestedAndExpectedToVestOutstandingNumber
Estimated Stock Based Compensation Expense Up On Vesting Of Options 327,000clrb_EstimatedStockBasedCompensationExpenseUpOnVestingOfOptions
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized $ 1,386,000us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
Minimum [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures Rate 0.00%clrb_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresRate
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Maximum [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures Rate 2.00%clrb_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresRate
/ us-gaap_RangeAxis
= us-gaap_MaximumMember