Name:	arcb_DebtInstrumentInterestRateEffectiveFixedPercentageOnHedgedBalance
Namespace Prefix:	arcb_
Data Type:	num:percentItemType
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Period Type:	instant

-- None. No documentation exists for this element. --

No definition available.

Name:	arcb_MaturitiesOfLongTermDebtAndFutureMinimumPaymentsUnderCapitalLeasesAbstract
Namespace Prefix:	arcb_
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Represents aggregate future amounts due of contractually required rental payments on leases meeting the criteria for capitalization and maturities on long-term debt, including interest.

No definition available.

Name:	arcb_MaturitiesOfLongTermDebtAndFutureMinimumPaymentsUnderCapitalLeasesDue
Namespace Prefix:	arcb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents amount of contractually required rental payments on leases meeting the criteria for capitalization and maturities on long-term debt, including interest, due within one year of the latest balance sheet date presented.

No definition available.

Name:	arcb_MaturitiesOfLongTermDebtAndFutureMinimumPaymentsUnderCapitalLeasesDueCurrent
Namespace Prefix:	arcb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents amount of contractually required rental payments on leases meeting the criteria for capitalization and maturities on long-term debt, including interest, due after four and within five years of the latest balance sheet date presented.

No definition available.

Name:	arcb_MaturitiesOfLongTermDebtAndFutureMinimumPaymentsUnderCapitalLeasesDueInFiveYears
Namespace Prefix:	arcb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents amount of contractually required rental payments on leases meeting the criteria for capitalization and maturities on long-term debt, including interest, due after three and within four years of the latest balance sheet date presented.

No definition available.

Name:	arcb_MaturitiesOfLongTermDebtAndFutureMinimumPaymentsUnderCapitalLeasesDueInFourYears
Namespace Prefix:	arcb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents amount of contractually required rental payments on leases meeting the criteria for capitalization and maturities on long-term debt, including interest, due after two and within three years of the latest balance sheet date presented.

No definition available.

Name:	arcb_MaturitiesOfLongTermDebtAndFutureMinimumPaymentsUnderCapitalLeasesDueInThreeYears
Namespace Prefix:	arcb_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Represents amount of contractually required rental payments on leases meeting the criteria for capitalization and maturities on long-term debt, including interest, due after one and within two years of the latest balance sheet date presented.

No definition available.

Name:	arcb_MaturitiesOfLongTermDebtAndFutureMinimumPaymentsUnderCapitalLeasesDueInTwoYears
Namespace Prefix:	arcb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents the interest amount by which the contractually required payments on capital leases and long-term debt are reduced to calculate the present value of the long-term debt and capital lease obligations.

No definition available.

Name:	arcb_MaturitiesOfLongTermDebtAndFutureMinimumPaymentsUnderCapitalLeasesInterestIncludedInPayments
Namespace Prefix:	arcb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6036836-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

Name:	us-gaap_DebtInstrumentLineItems
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Data Type:	xbrli:stringItemType
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Period Type:	duration

Weighted average interest rate of debt outstanding.

No definition available.

Name:	us-gaap_DebtWeightedAverageInterestRate
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Data Type:	num:percentItemType
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Amount of hedged item in hedging relationship. Excludes hedged asset or liability.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

Amount of long-term debt and lease obligation, classified as noncurrent.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
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Amount of long-term debt and lease obligation, classified as current.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Data Type:	xbrli:monetaryItemType
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Amount of long-term debt and lease obligation, including portion classified as current.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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