Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 820
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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.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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Investments Held In Trusts

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Trading Security, Fair Value

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Investment Securities - Investments In Private Equity Funds Subject to Lock-Up Periods (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Investment securities
Investments held in trusts	$ 479.5	$ 432.4
Lloyds Bank
Investment securities
Investments held in trusts	113.8
Fair value investments	342.8
Bank loan fund
Investment securities
Fair value investments	163.0
ILS funds
Investment securities
Fair value investments	51.9
Short-term investments
Investment securities
Investments pledged as collateral	50.0
Private equity funds
Investment securities
Trading security, fair value	141.8
1 – 3 years \| Private equity funds
Investment securities
Trading security, fair value	0.1
3 – 5 years \| Private equity funds
Investment securities
Trading security, fair value	13.9
5 – 10 years \| Private equity funds
Investment securities
Trading security, fair value	116.3
>10 years \| Private equity funds
Investment securities
Trading security, fair value	$ 11.5
Minimum
Investment securities
Redemptions and advanced redemption notice period	30 days
Maximum
Investment securities
Redemptions and advanced redemption notice period	90 days