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Accident and Workers' Compensation Insurance Liabilities (Details) - USD ($) $ in Millions | Dec. 31, 2016 | Dec. 31, 2015
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Accident and Workers' Compensation Insurance Liabilities [Line Items] |  |
Excess Insurance Coverage Limit | $ 100.0 |
Trust fund requirements | 0.7 |
Restricted Cash and Cash Equivalents, Noncurrent | 12.4 | $ 11.4
Letters of Credit Outstanding, Amount | 8.6 |
Auto liability retention limit minimum [Member] |  |
Accident and Workers' Compensation Insurance Liabilities [Line Items] |  |
Auto liability retention limit | 0.5 |
Auto liability retention limit maximum [Member] [Member] |  |
Accident and Workers' Compensation Insurance Liabilities [Line Items] |  |
Auto liability retention limit | 2.0 |
workers compensation retention limit minimum [Member] |  |
Accident and Workers' Compensation Insurance Liabilities [Line Items] |  |
Workers compensation retention limit | 0.5 |
workers compensation retention limit maximum [Member] |  |
Accident and Workers' Compensation Insurance Liabilities [Line Items] |  |
Workers compensation retention limit | 1.0 |
Gordon Trucking Company, Inc [Member] |  |
Accident and Workers' Compensation Insurance Liabilities [Line Items] |  |
Trust fund requirements | 0.6 |
Restricted Cash and Cash Equivalents, Noncurrent | $ 0.6 | $ 0.7

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- Definition Cash and equivalents whose use in whole or in part is restricted for the long-term, generally by contractual agreements or regulatory requirements. + 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 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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