Quarterly report pursuant to Section 13 or 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 $)
Mar. 31, 2015
Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost $ 15,898,000us-gaap_AvailableForSaleSecuritiesAmortizedCost $ 17,264,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
Gross Unrealized Gains 16,000jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax 7,000jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
Gross Unrealized Losses (9,000)jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax (55,000)jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Fair Value 15,905,000us-gaap_AvailableForSaleSecuritiesDebtSecurities 17,216,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
Cash Equivalents 442,000us-gaap_CashEquivalentsAtCarryingValue 1,073,000us-gaap_CashEquivalentsAtCarryingValue
Short-Term Investments 4,878,321us-gaap_ShortTermInvestments 4,602,717us-gaap_ShortTermInvestments
Long-Term Investments 10,585,239us-gaap_LongTermInvestments 11,540,261us-gaap_LongTermInvestments
Cash And Cash Equivalents [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 442,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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1,073,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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Fair Value 442,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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1,073,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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Cash Equivalents 442,000us-gaap_CashEquivalentsAtCarryingValue
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1,073,000us-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 442,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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1,073,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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Fair Value 442,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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1,073,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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Cash Equivalents 442,000us-gaap_CashEquivalentsAtCarryingValue
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1,073,000us-gaap_CashEquivalentsAtCarryingValue
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Investments [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 15,456,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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16,191,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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Gross Unrealized Gains 16,000jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
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7,000jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
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Gross Unrealized Losses (9,000)jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
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(55,000)jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
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Fair Value 15,463,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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16,143,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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Short-Term Investments 4,878,000us-gaap_ShortTermInvestments
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4,603,000us-gaap_ShortTermInvestments
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Long-Term Investments 10,585,000us-gaap_LongTermInvestments
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11,540,000us-gaap_LongTermInvestments
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Investments [Member] | Certificates Of Deposit [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 6,693,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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7,414,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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Gross Unrealized Gains 9,000jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
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1,000jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
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Gross Unrealized Losses (3,000)jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
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(32,000)jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
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Fair Value 6,699,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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7,383,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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Short-Term Investments 1,683,000us-gaap_ShortTermInvestments
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1,920,000us-gaap_ShortTermInvestments
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Long-Term Investments 5,016,000us-gaap_LongTermInvestments
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5,463,000us-gaap_LongTermInvestments
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Investments [Member] | Corporate Notes/Bonds [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 8,763,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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8,777,000us-gaap_AvailableForSaleSecuritiesAmortizedCost
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Gross Unrealized Gains 7,000jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
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6,000jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
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Gross Unrealized Losses (6,000)jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
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(23,000)jcs_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
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Fair Value 8,764,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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8,760,000us-gaap_AvailableForSaleSecuritiesDebtSecurities
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Short-Term Investments 3,195,000us-gaap_ShortTermInvestments
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2,683,000us-gaap_ShortTermInvestments
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Long-Term Investments $ 5,569,000us-gaap_LongTermInvestments
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$ 6,077,000us-gaap_LongTermInvestments
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