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Accident and Workers' Compensation Insurance Liabilities (Details) (USD $) In Millions, unless otherwise specified | Dec. 31, 2011 | Mar. 31, 2009
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Accident and Workers' Compensation Insurance Liabilities |  |
Auto liability retention limit | $ 2.0 | $ 1.0
Excess Insurance Coverage Limit | 55.0 |
Workers compensation retention limit | 1.0 |
Trust fund requirements | 0.7 |
Trust fund actual deposits | 1.3 |
Letters of Credit Outstanding, Amount | $ 3.1 |

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- Details
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- Definition Auto liability retention limit + References No definition available. + Details
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- Definition Excess Insurance Coverage Limit + References No definition available. + Details
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- Definition Trust fund actual deposits + References No definition available. + Details
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- Definition Trust fund requirements + References No definition available. + Details
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- Definition Workers compensation retention limit + References No definition available. + Details
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- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. + References No definition available. + Details
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