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Business Combinations - Schedule of Transaction Costs Associated with Acquisition (Details) - CH2M HILL Companies, Ltd. - USD ($) $ in Millions | 12 Months Ended
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Sep. 28, 2018 | Sep. 29, 2017
Business Acquisition [Line Items] |  |
Personnel costs | $ 50.2 | $ 2.2
Professional services and other expenses | 27.5 | 14.9
Total | $ 77.7 | $ 17.1

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- Definition Transaction costs (personnel costs) associated with a business acquisition which have been expensed during the period. + References No definition available. + Details
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- Definition Transaction costs (Professional service and real estate related and other expenses) associated with a business acquisition which have been expensed during the period. + References No definition available. + Details
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- Definition 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. + References No definition available. + Details
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- Definition Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs. + References No definition available. + Details
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- Details
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