Commitments and contingencies (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Sep. 30, 2016 |
Sep. 30, 2015 |
Sep. 30, 2014 |
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| Performance bonds | |||
| Performance bond commitments | $ 23.0 | ||
| Operating Lease expense | 75.4 | $ 67.1 | $ 61.8 |
| Operating sublease income | 1.1 | ||
| Sublease income | $ 1.2 | ||
| Percentage of employees covered by collective bargaining agreements | 16.00% | ||
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- Definition Amount of sublease rentals anticipated to be received during the next five fiscal years. No definition available.
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- Definition The percentage of employees covered by collective bargaining agreements as of the balance sheet date when it serves as a benchmark in a concentration of risk calculation. No definition available.
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- Definition The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition The amount of revenue recognized for the period under subleasing arrangements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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