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Investment Securities - Investments Held on Deposit or as Collateral (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021
Investment securities |  |
Percentage of investments recorded at fair value | 72.00% | 68.00%
Investments held in trusts | $ 500.5 | $ 479.5
Assets held by insurance regulators | 4.6 | 4.8
Outrigger Re | Cash and Short Term Investments |  |
Investment securities |  |
Investment owned, balance | 203.7 |
HG Global Senior Notes | Secured Debt |  |
Investment securities |  |
Interest reserve account | 31.2 |
Letter of Credit | Short-term investments | Asset Pledged as Collateral |  |
Investment securities |  |
Investments pledged as collateral | 90.3 | 50.0
Lloyds Bank |  |
Investment securities |  |
Investments held in trusts | 137.4 | 113.8
Fair value investments | $ 319.2 | $ 342.8

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- Definition Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 825 -Section 50 -Paragraph 1A -URI https://asc.fasb.org/extlink&oid=123600598&loc=SL75763979-209797 + Details
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- Definition The amount of cash, securities, or other assets held by a third-party trustee pursuant to the terms of an agreement which assets are available to be used by beneficiaries to that agreement only within the specific terms thereof and which agreement is expected to terminate within one year of the balance sheet date (or operating cycle, if longer) at which time the assets held-in-trust will be released or forfeited. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(b)) -URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 + Details
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- Definition The aggregate fair value as of the balance sheet date of financial instruments and other positions owned by the entity including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities. Includes both pledged and unpledged holdings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 320 -Section 45 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=35711157&loc=d3e42546-110969 + Details
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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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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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