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ACCOUNTING POLICIES (Details) (Minimum) | 12 Months Ended
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Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Revenues | Customer concentration risk |  |  |
Concentration of Credit Risk |  |  |
Percentage for concentration of credit risk disclosure | 5.00%arcb_ThresholdForDisclosurePercentage / us-gaap_ConcentrationRiskByBenchmarkAxis = us-gaap_SalesRevenueServicesNetMember / us-gaap_ConcentrationRiskByTypeAxis = us-gaap_CustomerConcentrationRiskMember / us-gaap_RangeAxis = us-gaap_MinimumMember | 5.00%arcb_ThresholdForDisclosurePercentage / us-gaap_ConcentrationRiskByBenchmarkAxis = us-gaap_SalesRevenueServicesNetMember / us-gaap_ConcentrationRiskByTypeAxis = us-gaap_CustomerConcentrationRiskMember / us-gaap_RangeAxis = us-gaap_MinimumMember | 5.00%arcb_ThresholdForDisclosurePercentage / us-gaap_ConcentrationRiskByBenchmarkAxis = us-gaap_SalesRevenueServicesNetMember / us-gaap_ConcentrationRiskByTypeAxis = us-gaap_CustomerConcentrationRiskMember / us-gaap_RangeAxis = us-gaap_MinimumMember
Accounts receivable | Credit concentration risk |  |  |
Concentration of Credit Risk |  |  |
Percentage for concentration of credit risk disclosure | 5.00%arcb_ThresholdForDisclosurePercentage / us-gaap_ConcentrationRiskByBenchmarkAxis = us-gaap_AccountsReceivableMember / us-gaap_ConcentrationRiskByTypeAxis = us-gaap_CreditConcentrationRiskMember / us-gaap_RangeAxis = us-gaap_MinimumMember | 5.00%arcb_ThresholdForDisclosurePercentage / us-gaap_ConcentrationRiskByBenchmarkAxis = us-gaap_AccountsReceivableMember / us-gaap_ConcentrationRiskByTypeAxis = us-gaap_CreditConcentrationRiskMember / us-gaap_RangeAxis = us-gaap_MinimumMember |

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- Definition Threshold percentage which the entity uses for disclosure. + References No definition available. + Details
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Balance Type: | na
Period Type: | duration

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Namespace Prefix: |
Data Type: | na
Balance Type: |
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- Details
Name: | us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_SalesRevenueServicesNetMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |