Securities and Commodity Financing Transactions - Schedule of Netting of Securities Purchased Under Agreements (Details) - USD ($) $ in Millions |
Jun. 30, 2026 |
Sep. 30, 2025 |
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| Broker-Dealer [Abstract] | ||
| Securities purchased under agreements to resell, gross | $ 34,206.3 | $ 26,298.1 |
| Securities purchased under agreements to resell, offset | (18,385.8) | (15,972.7) |
| Securities purchased under agreements to resell, net | 15,820.5 | 10,325.4 |
| Securities borrowed, gross | 3,007.2 | 2,743.1 |
| Securities borrowed, net | 3,007.2 | 2,743.1 |
| Securities sold under agreements to repurchase, gross | 36,381.9 | 29,523.7 |
| Securities sold under agreements to repurchase, offset | (18,385.8) | (15,972.7) |
| Securities sold under agreements to repurchase, net | 17,996.1 | 13,551.0 |
| Securities loaned, gross | 2,955.7 | 2,550.8 |
| Securities loaned, net | $ 2,955.7 | $ 2,550.8 |
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- References No definition available.
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- Definition Amount, after the effects of master netting arrangements, of securities borrowed from entities in exchange for collateral. Includes assets not subject to a master netting arrangement and not elected to be offset. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, before effects of master netting arrangements, of securities borrowed from entities in exchange for collateral. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition Amount, after the effects of master netting arrangements, of securities loaned to entities in exchange for collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition Amount, before effects of master netting arrangements, of securities loaned to entities in exchange for collateral. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after the effects of master netting arrangements, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes purchases of participations in pools of securities that are subject to a resale agreement, assets not subject to a master netting arrangement and not elected to be offset. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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| X | ||||||||||
- Definition Amount, before effects of master netting arrangements, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of liability associated with funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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| X | ||||||||||
- Definition Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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| X | ||||||||||
- Definition Amount of asset associated with funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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| X | ||||||||||
- Definition Amount, before effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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