XML 44 R73.htm IDEA: XBRL DOCUMENT v2.4.1.9
Subsequent Events - Additional Information (Detail) (USD $)
0 Months Ended 12 Months Ended
Jan. 08, 2015
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Subsequent Event [Line Items]        
Proceeds from Issuance or Sale of Equity $ 30,000,000us-gaap_ProceedsFromIssuanceOrSaleOfEquity      
Debt Instrument, interest rate terms The Term Loan will mature on July 1, 2018. Each advance under the Term Loan accrues interest at a floating per annum rate equal to the greater of (i) 7.30% or (ii) the sum of 7.30% plus the prime rate minus 5.75%. The Term Loan provides for interest-only payments on a monthly basis until December 31, 2015      
Long-term debt, maturities, prepayment terms   Any such prepayment of the Term Loan is subject to a prepayment charge of (i) 3.0% if such prepayment occurs within twelve months of the Closing Date, (ii) 2.0% if such prepayment occurs after twelve months following the Closing Date but on or prior to twenty-four months following the Closing Date, and (iii) 1.0% thereafter    
Additional interest rate accrue on default   5.00%ceru_DebtInstrumentAdditionalInterestRateAccrueOnDefault    
Interest rate of final payment on principal amount   6.70%ceru_DebtInstrumentInterestRateOfFinalPaymentOnPrincipalAmount    
Purchase of common stock, shares   20,125,049us-gaap_CommonStockSharesIssued 785,531us-gaap_CommonStockSharesIssued  
Proceeds from sale of common stock   140,000us-gaap_ProceedsFromIssuanceOfCommonStock 35,000us-gaap_ProceedsFromIssuanceOfCommonStock 3,000us-gaap_ProceedsFromIssuanceOfCommonStock
Subsequent Event        
Subsequent Event [Line Items]        
Number of tranches 3ceru_NumberOfTranches
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
     
Subsequent Event | Maximum [Member]        
Subsequent Event [Line Items]        
Proceeds from Issuance or Sale of Equity 40,000,000us-gaap_ProceedsFromIssuanceOrSaleOfEquity
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
     
Subsequent Event | Minimum [Member]        
Subsequent Event [Line Items]        
Amount of term loan facility required to be drawn 3,000,000ceru_AmountOfTermLoanFacilityRequiredToBeDrawn
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
     
Hercules Technology Growth Capital, Inc. [Member] | Subsequent Event        
Subsequent Event [Line Items]        
Loan and security agreement, maximum borrowing capacity 26,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_LineOfCreditFacilityAxis
= ceru_HerculesTechnologyGrowthCapitalIncMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
     
Common stock per share $ 6.05us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
/ us-gaap_LineOfCreditFacilityAxis
= ceru_HerculesTechnologyGrowthCapitalIncMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
     
Conversion of preferred warrants to common warrants. 137,521us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
/ us-gaap_LineOfCreditFacilityAxis
= ceru_HerculesTechnologyGrowthCapitalIncMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
     
Class of additional warrant or right number of securities called by warrants or rights 34,380ceru_ClassOfAdditionalWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
/ us-gaap_LineOfCreditFacilityAxis
= ceru_HerculesTechnologyGrowthCapitalIncMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
     
Class of warrant or right, date from which warrants or rights exercisable Jan. 08, 2020      
Purchase of common stock, shares 135,501us-gaap_CommonStockSharesIssued
/ us-gaap_LineOfCreditFacilityAxis
= ceru_HerculesTechnologyGrowthCapitalIncMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
     
Purchase price of common share $ 7.38us-gaap_SharesIssuedPricePerShare
/ us-gaap_LineOfCreditFacilityAxis
= ceru_HerculesTechnologyGrowthCapitalIncMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
     
Proceeds from sale of common stock 1,000,000us-gaap_ProceedsFromIssuanceOfCommonStock
/ us-gaap_LineOfCreditFacilityAxis
= ceru_HerculesTechnologyGrowthCapitalIncMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
     
Borrowings One [Member] | Subsequent Event        
Subsequent Event [Line Items]        
Loan and security agreement, maximum borrowing capacity 15,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_LineOfCreditFacilityAxis
= ceru_BorrowingsOneMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
     
Borrowings Two [Member] | Subsequent Event        
Subsequent Event [Line Items]        
Loan and security agreement, maximum borrowing capacity 5,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_LineOfCreditFacilityAxis
= ceru_BorrowingsTwoMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
     
Borrowings Three [Member] | Subsequent Event        
Subsequent Event [Line Items]        
Loan and security agreement, maximum borrowing capacity $ 6,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_LineOfCreditFacilityAxis
= ceru_BorrowingsThreeMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember