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Financial Instruments with Off-Balance Sheet Risk and Concentrations of Credit Risk - Derivatives Volume (Details) number in Millions | Dec. 31, 2017 | Sep. 30, 2017
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Financial Instruments with Off-Balance Sheet Risk and Concentrations of Credit Risk [Abstract] |  |
Derivative, Number of Instruments Held | 6.8 | 6.1

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- Definition Financial Instruments with Off-Balance Sheet Risk and Concentrations of Credit Risk [Abstract] + References No definition available. + Details
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- Definition The number of derivative instruments of a particular group held by the entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5579245-113959 + Details
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