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Investment Securities - Investments In Private Equity Funds Subject to Lock-Up Periods (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021
Investment securities |  |
Investments held in trusts | $ 500.5 | $ 479.5
Lloyds Bank |  |
Investment securities |  |
Fair value investments | 319.2 | 342.8
Investments held in trusts | 137.4 | $ 113.8
Bank loan fund |  |
Investment securities |  |
Fair value investments | 174.8 |
ILS funds |  |
Investment securities |  |
Fair value investments | 49.3 |
Commitments to funds | 100.0 |
Insurance-Linked Securities Funds Receivable |  |
Investment securities |  |
Fair value investments | 70.0 |
Private equity funds |  |
Investment securities |  |
Trading security, fair value | 140.6 |
1 – 3 years | Private equity funds |  |
Investment securities |  |
Trading security, fair value | 4.2 |
3 – 5 years | Private equity funds |  |
Investment securities |  |
Trading security, fair value | 18.8 |
5 – 10 years | Private equity funds |  |
Investment securities |  |
Trading security, fair value | 113.9 |
>10 years | Private equity funds |  |
Investment securities |  |
Trading security, fair value | $ 3.7 |

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- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258 + Details
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