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Receivables From Customers, Net and Notes Receivable, Net Receivables from Customers, Net and Notes Receivables, Net - Bad Debt Expense and Recoveries (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Jun. 30, 2015 | Jun. 30, 2016 | Jun. 30, 2015
Allowance for Doubtful Accounts Receivable, Period Increase (Decrease) |  |  | $ 2.8
Provision for Doubtful Accounts | $ 0.4 | $ 4.6 | 3.2
Securities [Member] |  |  |
Allowance for Doubtful Accounts Receivable, Period Increase (Decrease) |  | 0.3 |
Commercial Hedging [Member] |  |  |
Allowance for Doubtful Accounts Receivable, Period Increase (Decrease) |  | 2.7 |
Allowance for Doubtful Accounts Receivable, Write-offs |  |  | $ 0.4
Physical Commodities [Member] |  |  |
Allowance for Doubtful Accounts Receivable, Period Increase (Decrease) |  | $ 1.5 |

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- Definition Amount of direct write-downs of accounts receivable charged against the allowance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 954 -SubTopic 310 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=51673446&loc=SL9156395-115594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5074-111524 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.4) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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