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Debt - Other Debt (Details) - Other Debt - Standby letter of credit - USD ($) $ in Millions | Mar. 31, 2018 | Sep. 30, 2017
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Debt |  |
Outstanding letters of credit | $ 455.1 | $ 445.7
Remaining borrowing capacity under credit facility | $ 482.7 |

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Balance Type: | na
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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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Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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- Definition Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding). + 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 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Details
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- Details
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