Income taxes - Narrative (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Sep. 30, 2017 |
Sep. 30, 2016 |
Sep. 30, 2015 |
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| Net operating loss carryforwards | |||
| Cumulative earnings from foreign subsidiaries | $ 219.0 | ||
| Income taxes paid | 87.8 | $ 108.3 | $ 81.3 |
| Unrecognized tax benefits | |||
| Unrecognized tax benefits that, if recognized, would affect the annual effective income tax rate | 1.1 | 1.1 | |
| Interest and penalties included in net liability balance | 0.6 | 0.6 | |
| Maximum | |||
| Unrecognized tax benefits | |||
| Interest expense recognized related to unrecognized tax benefits | $ 0.1 | $ 0.1 | $ 0.1 |
| X | ||||||||||
- Definition Represents Unrepatriated foreign earnings, upon which no federal or state taxes have been provided, that are considered to be permanently reinvested abroad, as of the balance sheet date. No definition available.
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- Definition The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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. No definition available.
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- Definition Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount of interest expense for an underpayment of income taxes. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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