Commodity and Other Repurchase Agreements Commodity and Other Repurchase Agreements (Details) - USD ($) $ in Millions	Dec. 31, 2018	Sep. 30, 2018
Fair Value of Securities Received as Collateral that Can be Resold or Repledged	$ 1,959.7	$ 1,294.8
Fair Value of Securities Received as Collateral that Have Been Resold or Repledged	429.7	473.9
Financing Receivables, net - Sales/Repurchase Agreements	0.7	1.9
Financial Instruments Owned and Pledged as Collateral, Amount Eligible to be Repledged by Counterparty	320.9	123.0
Securities Loaned, Fair Value of Collateral	1,018.1	267.9
Securities Sold under Agreements to Repurchase, Fair Value of Collateral	320.9	123.0
Trading Securities Pledged as Collateral	1,212.2	1,481.1
Pledged Assets Separately Reported, Securities Pledged for Repurchase Agreements, at Fair Value	$ 752.6	$ 369.8

Financing Receivables, net - Sales/Repurchase Agreements

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- Definition

Fair value of collateral permitted, by contact or custom, to be sold or re-pledged.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=64858031&loc=SL6224234-111729

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- Definition

Fair value of the collateral, or portion thereof, that has been re-pledged, delivered, or otherwise used.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=64858031&loc=SL6224234-111729

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- Definition

Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions where counterparty has the right to re-pledge such.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728

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- Definition

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=64858031&loc=SL6224234-111729

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- Definition

The fair value, as of the date of each statement of financial position presented, of securities which are owned but transferred to serve as collateral for the payment of repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

+ References

+ Details

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- Definition

Fair value of the securities pledged as collateral against securities loaned.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226013-175313

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- Definition

Fair value of securities pledged as collateral against securities sold under agreement to repurchase.

+ References

+ Details

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