v2.4.0.6

Loss of Significant Agent's brokerage division busines (Detail) (USD $) | 12 Months Ended
--- | ---
Dec. 31, 2011
Business Acquisition |  |
Total revenues | $ (253,942,000) |
Cost of transportation | (203,042,000) |
Commissions | (31,601,000) |
Operating expenses | (12,274,000) |
Agent's brokerage division business |  |
Business Acquisition |  |
Total revenues | 66,028,000 |
Cost of transportation | 56,451,000 | [1]
Commissions | 8,225,000 | [1]
Operating expenses | $ 366,000 | [1]
[1] | Represents the impact of the loss of the Significant Agent's brokerage division business, as follows:

X
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Period Type: | duration

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- Definition BusinessAcquisitionsProFormaOperating expenses impact of loss + References No definition available. + Details
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Namespace Prefix: | auto_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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- Definition BusinessAcquisitionsProFormaPurchased transportation + References No definition available. + Details
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Namespace Prefix: | auto_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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

X
- Definition The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(2)-(3) -URI http://asc.fasb.org/extlink&oid=7659399&loc=d3e1392-128463 + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
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