XML 31 R31.htm IDEA: XBRL DOCUMENT
v2.4.1.9

FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS (Details) (USD $) | Mar. 31, 2015 | Dec. 31, 2014 | Mar. 31, 2014 | Dec. 31, 2013
--- | --- | --- | --- | ---
Fair value disclosure |  |  |  |
Cash and cash equivalents | $ 166,022,000 us-gaap_CashAndCashEquivalentsAtCarryingValue | $ 157,042,000 us-gaap_CashAndCashEquivalentsAtCarryingValue | $ 95,728,000 us-gaap_CashAndCashEquivalentsAtCarryingValue | $ 105,354,000 us-gaap_CashAndCashEquivalentsAtCarryingValue
Short-term investments | 45,980,000 us-gaap_ShortTermInvestments | 45,909,000 us-gaap_ShortTermInvestments |  |
Restricted cash | 1,386,000 us-gaap_RestrictedCashAndInvestmentsCurrent | 1,386,000 us-gaap_RestrictedCashAndInvestmentsCurrent |  |
Concentrations of Credit Risk of Financial Instruments |  |  |  |
Cash and cash equivalents which are not FDIC-insured | 84,700,000 arcb_DepositsUninsuredAmount | 77,300,000 arcb_DepositsUninsuredAmount |  |
Fair value disclosure |  |  |  |
Fair value disclosure |  |  |  |
Cash and cash equivalents | 166,022,000 us-gaap_CashAndCashEquivalentsAtCarryingValue / us-gaap_FairValueByMeasurementBasisAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember | 157,042,000 us-gaap_CashAndCashEquivalentsAtCarryingValue / us-gaap_FairValueByMeasurementBasisAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember |  |
Fair value disclosure | Cash deposits |  |  |  |
Fair value disclosure |  |  |  |
Cash and cash equivalents | 103,579,000 us-gaap_CashAndCashEquivalentsAtCarryingValue / us-gaap_FairValueByMeasurementBasisAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_InvestmentTypeAxis = us-gaap_CashMember | 99,615,000 us-gaap_CashAndCashEquivalentsAtCarryingValue / us-gaap_FairValueByMeasurementBasisAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_InvestmentTypeAxis = us-gaap_CashMember |  |
Restricted cash | 1,386,000 us-gaap_RestrictedCashAndInvestmentsCurrent / us-gaap_FairValueByMeasurementBasisAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_InvestmentTypeAxis = us-gaap_CashMember | 1,386,000 us-gaap_RestrictedCashAndInvestmentsCurrent / us-gaap_FairValueByMeasurementBasisAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_InvestmentTypeAxis = us-gaap_CashMember |  |
Fair value disclosure | Variable rate demand notes |  |  |  |
Fair value disclosure |  |  |  |
Cash and cash equivalents | 16,342,000 us-gaap_CashAndCashEquivalentsAtCarryingValue / us-gaap_FairValueByMeasurementBasisAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_InvestmentTypeAxis = us-gaap_VariableRateDemandObligationMember | 16,326,000 us-gaap_CashAndCashEquivalentsAtCarryingValue / us-gaap_FairValueByMeasurementBasisAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_InvestmentTypeAxis = us-gaap_VariableRateDemandObligationMember |  |
Fair value disclosure | Money market funds |  |  |  |
Fair value disclosure |  |  |  |
Cash and cash equivalents | 46,101,000 us-gaap_CashAndCashEquivalentsAtCarryingValue / us-gaap_FairValueByMeasurementBasisAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_InvestmentTypeAxis = us-gaap_MoneyMarketFundsMember | 41,101,000 us-gaap_CashAndCashEquivalentsAtCarryingValue / us-gaap_FairValueByMeasurementBasisAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_InvestmentTypeAxis = us-gaap_MoneyMarketFundsMember |  |
Fair value disclosure | Certificates of deposit |  |  |  |
Fair value disclosure |  |  |  |
Short-term investments | $ 45,980,000 us-gaap_ShortTermInvestments / us-gaap_FairValueByMeasurementBasisAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_InvestmentTypeAxis = us-gaap_CertificatesOfDepositMember | $ 45,909,000 us-gaap_ShortTermInvestments / us-gaap_FairValueByMeasurementBasisAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_InvestmentTypeAxis = us-gaap_CertificatesOfDepositMember |  |

X
- Definition The amount of cash and cash equivalents as of the balance sheet date that is not insured by the Federal Deposit Insurance Corporation. + References No definition available. + Details
Name: | arcb_DepositsUninsuredAmount
Namespace Prefix: | arcb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash -URI http://asc.fasb.org/extlink&oid=6506951 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash Equivalents -URI http://asc.fasb.org/extlink&oid=6507016 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6676-107765 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3044-108585 + Details
Name: | us-gaap_CashAndCashEquivalentsAtCarryingValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_ConcentrationRisksTypesNoConcentrationPercentageAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The current cash, cash equivalents and investments that are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. Includes current cash equivalents and investments that are similarly restricted as to withdrawal, usage or disposal. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_RestrictedCashAndInvestmentsCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Investments which are intended to be sold in the short term (usually less than one year or the normal operating cycle, whichever is longer) including trading securities, available-for-sale securities, held-to-maturity securities, and other short-term investments not otherwise listed in the existing taxonomy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph g -Article 7 + Details
Name: | us-gaap_ShortTermInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FairValueByMeasurementBasisAxis=us-gaap_EstimateOfFairValueFairValueDisclosureMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |