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Intangible Assets Intangible Asset Additions (Details) $ in Millions | 12 Months Ended
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Sep. 30, 2019 USD ($)
Business Acquisition [Line Items] |
Indefinite-lived Intangible Assets Acquired | $ 2.7
Coininvest and European Precious Metals Trading [Member] |
Business Acquisition [Line Items] |
Finite-lived Intangible Assets Acquired | 2.6
Indefinite-lived Intangible Assets Acquired | 2.1
Fillmore Advisors, LLC [Member] |
Business Acquisition [Line Items] |
Finite-lived Intangible Assets Acquired | 0.7
Akshay Financeware, Inc. Acquisition [Member] |
Business Acquisition [Line Items] |
Indefinite-lived Intangible Assets Acquired | $ 2.7

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- Definition Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275 + Details
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