Annual report pursuant to Section 13 and 15(d)

Cash Equivalents And Investments (Schedule Of Available-For-Sale Securities) (Details)

v2.4.1.9
Cash Equivalents And Investments (Schedule Of Available-For-Sale Securities) (Details) (USD $)
Dec. 31, 2014
Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost $ 17,264,000us-gaap_AvailableForSaleSecuritiesAmortizedCost $ 15,637,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
Gross Unrealized Gains 7,000jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax 24,000jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
Gross Unrealized Losses (55,000)jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax (6,000)jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Fair Value 17,216,000us-gaap_AvailableForSaleSecuritiesDebtSecurities 15,655,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
Cash Equivalents 1,073,000us-gaap_CashEquivalentsAtCarryingValue 5,992,000us-gaap_CashEquivalentsAtCarryingValue
Short-Term Investments 4,602,717us-gaap_ShortTermInvestments 5,742,314us-gaap_ShortTermInvestments
Long-Term Investments 11,540,261us-gaap_LongTermInvestments 3,920,978us-gaap_LongTermInvestments
Cash And Cash Equivalents [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 1,073,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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5,752,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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Fair Value 1,073,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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5,752,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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Cash Equivalents 1,073,000us-gaap_CashEquivalentsAtCarryingValue
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5,752,000us-gaap_CashEquivalentsAtCarryingValue
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Cash And Cash Equivalents [Member] | Money Market Funds [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 1,073,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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5,752,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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Fair Value 1,073,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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5,752,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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Cash Equivalents 1,073,000us-gaap_CashEquivalentsAtCarryingValue
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5,752,000us-gaap_CashEquivalentsAtCarryingValue
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Investments [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 16,191,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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9,885,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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Gross Unrealized Gains 7,000jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
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24,000jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
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Gross Unrealized Losses (55,000)jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
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(6,000)jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
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Fair Value 16,143,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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9,903,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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Cash Equivalents   240,000us-gaap_CashEquivalentsAtCarryingValue
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Short-Term Investments 4,603,000us-gaap_ShortTermInvestments
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5,742,000us-gaap_ShortTermInvestments
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Long-Term Investments 11,540,000us-gaap_LongTermInvestments
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3,921,000us-gaap_LongTermInvestments
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Investments [Member] | Certificates Of Deposit [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 7,414,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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4,024,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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Gross Unrealized Gains 1,000jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
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1,000jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
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Gross Unrealized Losses (32,000)jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
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(5,000)jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
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Fair Value 7,383,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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4,020,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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Cash Equivalents   240,000us-gaap_CashEquivalentsAtCarryingValue
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Short-Term Investments 1,920,000us-gaap_ShortTermInvestments
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2,583,000us-gaap_ShortTermInvestments
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Long-Term Investments 5,463,000us-gaap_LongTermInvestments
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1,197,000us-gaap_LongTermInvestments
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Investments [Member] | Corporate Notes/Bonds [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 8,777,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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5,861,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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Gross Unrealized Gains 6,000jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
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23,000jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
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Gross Unrealized Losses (23,000)jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
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(1,000)jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
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Fair Value 8,760,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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5,883,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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Short-Term Investments 2,683,000us-gaap_ShortTermInvestments
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3,159,000us-gaap_ShortTermInvestments
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Long-Term Investments $ 6,077,000us-gaap_LongTermInvestments
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$ 2,724,000us-gaap_LongTermInvestments
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