Quarterly report pursuant to Section 13 or 15(d)

Fair Value of Warrants - Assumptions Used in Computing Fair Value of Derivative Warrants (Detail)

v2.4.1.9
Fair Value of Warrants - Assumptions Used in Computing Fair Value of Derivative Warrants (Detail) (USD $)
3 Months Ended 12 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Dec. 31, 2014
Series B Preferred Stock [Member]      
Class of Warrant or Right [Line Items]      
Exercise Price $ 10.00cgix_FairValueAssumptionExercisePrice
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
$ 10.00cgix_FairValueAssumptionExercisePrice
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
$ 10.00cgix_FairValueAssumptionExercisePrice
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
Expected life (years) 7 months 17 days 1 year 8 months 19 days 10 months 17 days
Expected volatility 49.12%us-gaap_FairValueAssumptionsExpectedVolatilityRate
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
46.60%us-gaap_FairValueAssumptionsExpectedVolatilityRate
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
49.95%us-gaap_FairValueAssumptionsExpectedVolatilityRate
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
Risk-free interest rate 0.14%us-gaap_FairValueAssumptionsRiskFreeInterestRate
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
0.33%us-gaap_FairValueAssumptionsRiskFreeInterestRate
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
0.25%us-gaap_FairValueAssumptionsRiskFreeInterestRate
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
Expected dividend yield 0.00%us-gaap_FairValueAssumptionsExpectedDividendRate
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
0.00%us-gaap_FairValueAssumptionsExpectedDividendRate
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
0.00%us-gaap_FairValueAssumptionsExpectedDividendRate
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
Debt Guarantee [Member]      
Class of Warrant or Right [Line Items]      
Exercise Price   $ 10.00cgix_FairValueAssumptionExercisePrice
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_DebtRelatedGuaranteesMember
 
Expected life (years)   7 months 6 days  
Expected volatility   49.01%us-gaap_FairValueAssumptionsExpectedVolatilityRate
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_DebtRelatedGuaranteesMember
 
Risk-free interest rate   0.08%us-gaap_FairValueAssumptionsRiskFreeInterestRate
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_DebtRelatedGuaranteesMember
 
Expected dividend yield   0.00%us-gaap_FairValueAssumptionsExpectedDividendRate
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_DebtRelatedGuaranteesMember
 
Consulting [Member]      
Class of Warrant or Right [Line Items]      
Exercise Price $ 10.00cgix_FairValueAssumptionExercisePrice
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_ConsultantWarrantsMember
  $ 10.00cgix_FairValueAssumptionExercisePrice
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_ConsultantWarrantsMember
Expected life (years) 10 months 24 days   1 year 1 month 21 days
Expected volatility 46.92%us-gaap_FairValueAssumptionsExpectedVolatilityRate
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_ConsultantWarrantsMember
  49.25%us-gaap_FairValueAssumptionsExpectedVolatilityRate
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_ConsultantWarrantsMember
Risk-free interest rate 0.26%us-gaap_FairValueAssumptionsRiskFreeInterestRate
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_ConsultantWarrantsMember
  0.25%us-gaap_FairValueAssumptionsRiskFreeInterestRate
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_ConsultantWarrantsMember
Expected dividend yield 0.00%us-gaap_FairValueAssumptionsExpectedDividendRate
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_ConsultantWarrantsMember
  0.00%us-gaap_FairValueAssumptionsExpectedDividendRate
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_ConsultantWarrantsMember
Financing [Member]      
Class of Warrant or Right [Line Items]      
Exercise Price $ 10.00cgix_FairValueAssumptionExercisePrice
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_FinancialMember
  $ 10.00cgix_FairValueAssumptionExercisePrice
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_FinancialMember
Expected life (years) 11 months 23 days   1 year 2 months 23 days
Expected volatility 46.69%us-gaap_FairValueAssumptionsExpectedVolatilityRate
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_FinancialMember
  50.23%us-gaap_FairValueAssumptionsExpectedVolatilityRate
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_FinancialMember
Risk-free interest rate 0.26%us-gaap_FairValueAssumptionsRiskFreeInterestRate
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_FinancialMember
  0.25%us-gaap_FairValueAssumptionsRiskFreeInterestRate
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_FinancialMember
Expected dividend yield 0.00%us-gaap_FairValueAssumptionsExpectedDividendRate
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_FinancialMember
  0.00%us-gaap_FairValueAssumptionsExpectedDividendRate
/ us-gaap_SecuritiesFinancingTransactionAxis
= cgix_FinancialMember