Annual report pursuant to Section 13 and 15(d)

Stock Plans and Stock-Based Compensation - Summary of Stock Options Outstanding (Detail)

v2.4.1.9
Stock Plans and Stock-Based Compensation - Summary of Stock Options Outstanding (Detail) (USD $)
12 Months Ended
Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Option Outstanding Number of Shares 991,010us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions
Weighted-Average Remaining Contractual Term (Years) 8 years 10 months 28 days
Options Exercisable Number of Shares 515,908us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions
$4.77 [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Exercise Price 4.77us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceOneMember
Option Outstanding Number of Shares 10,983us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceOneMember
Weighted-Average Remaining Contractual Term (Years) 7 years 26 days
Options Exercisable Number of Shares 9,538us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceOneMember
$5.00 [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Exercise Price 5.00us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceTwoMember
Option Outstanding Number of Shares 867,782us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceTwoMember
Weighted-Average Remaining Contractual Term (Years) 8 years 11 months 9 days
Options Exercisable Number of Shares 499,625us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceTwoMember
$5.23 [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Exercise Price 5.23us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceThreeMember
Option Outstanding Number of Shares 10,000us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceThreeMember
Weighted-Average Remaining Contractual Term (Years) 9 years 7 months 24 days
$6.85 [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Exercise Price 6.85us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceFourMember
Option Outstanding Number of Shares 12,000us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceFourMember
Weighted-Average Remaining Contractual Term (Years) 9 years 8 months 23 days
$7.00 [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Exercise Price 7.00us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceFiveMember
Option Outstanding Number of Shares 77,000us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceFiveMember
Weighted-Average Remaining Contractual Term (Years) 9 years 3 months 11 days
$7.99 [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Exercise Price 7.99us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceSixMember
Option Outstanding Number of Shares 6,500us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceSixMember
Weighted-Average Remaining Contractual Term (Years) 9 years 4 months 10 days
$30.21 [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Exercise Price 30.21us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceSevenMember
Option Outstanding Number of Shares 3,290us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceSevenMember
Weighted-Average Remaining Contractual Term (Years) 7 days
Options Exercisable Number of Shares 3,290us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceSevenMember
$238.50 [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Exercise Price 238.50us-gaap_SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeOutstandingOptionsWeightedAverageExercisePriceBeginningBalance1
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceEightMember
Option Outstanding Number of Shares 3,455us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfOutstandingOptions
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceEightMember
Weighted-Average Remaining Contractual Term (Years) 1 year 8 months 23 days
Options Exercisable Number of Shares 3,455us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions
/ us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis
= cyma_ExercisePriceEightMember