Annual report pursuant to Section 13 and 15(d)

Fair Value Measurements (Narrative) (Details)

v2.4.1.9
Fair Value Measurements (Narrative) (Details) (USD $)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair value of accrued consideration   $ 559,000us-gaap_AccruedLiabilitiesFairValueDisclosure
Fair Value, Assets, Level 1 to Level 2 Transfers, amount 0us-gaap_FairValueAssetsLevel1ToLevel2TransfersAmount 0us-gaap_FairValueAssetsLevel1ToLevel2TransfersAmount
Fair Value, Assets, Level 2 to Level 1 Transfers, amount 0us-gaap_FairValueAssetsLevel2ToLevel1TransfersAmount 0us-gaap_FairValueAssetsLevel2ToLevel1TransfersAmount
Fair Value, Liabilities, Level 1 to Level 2 Transfers, amount 0us-gaap_FairValueLiabilitiesLevel1ToLevel2TransfersAmount 0us-gaap_FairValueLiabilitiesLevel1ToLevel2TransfersAmount
Fair Value, Liabilities, Level 2 to Level 1 Transfers, amount 0us-gaap_FairValueLiabilitiesLevel2ToLevel1TransfersAmount 0us-gaap_FairValueLiabilitiesLevel2ToLevel1TransfersAmount
Payments [Member]    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Change in fair value of acquisition-related contingent consideration due to payments (566,000)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements
/ us-gaap_ContingentConsiderationByTypeAxis
= jcs_PaymentsMember
 
Foreign Currency Gain (Loss) [Member]    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Change in fair value of acquisition-related contingent consideration due to payments (7,000)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements
/ us-gaap_ContingentConsiderationByTypeAxis
= us-gaap_ForeignCurrencyGainLossMember
 
Level 3 [Member]    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair value of accrued consideration   559,000us-gaap_AccruedLiabilitiesFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
Accrued Consideration [Member]    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair value of accrued consideration   559,000us-gaap_AccruedLiabilitiesFairValueDisclosure
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= jcs_AccruedConsiderationMember
Accrued Consideration [Member] | Level 3 [Member]    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair value of accrued consideration   $ 558,801us-gaap_AccruedLiabilitiesFairValueDisclosure
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= jcs_AccruedConsiderationMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member