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Goodwill (Tables) | 6 Months Ended
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Mar. 31, 2019
Goodwill [Abstract] |
Schedule of Goodwill [Table Text Block] | The carrying value of goodwill is allocated to the Company’s operating segments as follows:
(in millions) | March 31, 2019 |  | September 30, 2018
Commercial Hedging | $ | 30.3 |  |  | $ | 30.3 |
Global Payments | 6.9 |  |  | 8.9 |
Physical Commodities | 2.4 |  |  | 2.4 |
Securities | 7.0 |  |  | 6.8 |
Goodwill | $ | 46.6 |  |  | $ | 48.4 |

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- Definition Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267 + Details
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