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Debt - Narrative (Details) € in Millions |  |  |  |  | 1 Months Ended | 3 Months Ended |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
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Jan. 24, 2025 USD ($) | Apr. 29, 2022 USD ($) | Sep. 08, 2021 USD ($) | Aug. 11, 2021 USD ($) | Jul. 31, 2023 | Sep. 30, 2021 USD ($) | Jul. 31, 2021 | Mar. 31, 2025 USD ($) credit_facility | Mar. 31, 2024 USD ($) | Sep. 30, 2021 USD ($) transaction | Dec. 31, 2025 | Mar. 31, 2025 EUR (€) credit_facility | Mar. 18, 2025 | Mar. 12, 2025 USD ($) | Dec. 31, 2024 USD ($) | Sep. 17, 2024 USD ($) | Aug. 22, 2024 USD ($) | Jul. 31, 2024 | Jun. 28, 2024 USD ($) | Sep. 30, 2022 USD ($) | Jun. 16, 2022 USD ($) | Dec. 31, 2021 USD ($) | Jul. 13, 2021 USD ($) | Jul. 13, 2021 EUR (€) | Mar. 23, 2021 USD ($) | Mar. 31, 2007 USD ($)
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of notes |  |  |  |  |  |  |  | $ 1,000,000.0 | $ 32,600,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsidiary - HG Global | Interest Rate Cap |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Notional amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 150,000,000 |  |  |  | $ 150,000,000 |  |  |  |  |
Maximum interest rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10.76% |  |  |  | 9.76% |  |  |  |  |
Kudu | Interest Rate Cap |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Notional amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 150,000,000 |  |  |  |  |  |  |  |  |  |
Maximum interest rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 8.95% |  |  |  |  |  |  |  |  |  |
Subsidiary - Bamboo | Interest Rate Cap |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Notional amount |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 80,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Maximum interest rate |  |  |  |  |  |  |  |  |  |  |  |  |  | 10.00% |  |  |  |  |  |  |  |  |  |  |  |
Ark 2007 Subordinated Notes | Junior Subordinated Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 30,000,000
Repayments of notes |  |  |  |  |  |  |  |  | 30,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ark 2021 Subordinated Notes | Subordinated Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face value |  |  |  |  |  | $ 163,300,000 |  |  |  | $ 163,300,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of transactions | transaction |  |  |  |  |  |  |  |  |  | 3 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from debt, net of debt issuance costs |  |  |  |  |  |  |  |  |  | $ 157,800,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ark 2021 Subordinated Notes Tranche 1 | Subordinated Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 46,300,000 | € 39.1 |  |
Amount borrowed |  |  |  |  |  |  |  | 42,500,000 |  |  |  | € 39.1 |  |  | $ 41,100,000 |  |  |  |  |  |  |  |  |  |  |
Ark 2021 Subordinated Notes Tranche 1 | Subordinated Debt | Euro Interbank Offered Rate (EURIBOR) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  |  | 5.75% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ark 2021 Subordinated Notes Tranche 2 | Subordinated Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face value |  |  |  | $ 47,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amount borrowed |  |  |  |  |  |  |  | 47,000,000.0 |  |  |  |  |  |  | 47,000,000.0 |  |  |  |  |  |  |  |  |  |  |
Ark 2021 Subordinated Notes Tranche 2 | Subordinated Debt | London Interbank Offered Rate (LIBOR) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  | 5.75% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Kudu Credit Facility | Secured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 350,000,000 |  |  |  |  |  | $ 300,000,000 |
Repayments of notes |  |  |  |  |  |  |  | 0 | $ 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  | 0.26% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amount borrowed |  |  |  |  |  |  |  | 253,300,000 |  |  |  |  |  |  | 245,300,000 |  |  |  |  |  |  |  |  |  |  |
Stated margin |  |  |  |  | 4.30% |  |  |  |  |  |  |  |  |  |  |  |  | 4.45% |  |  |  |  |  |  |  |
Interest reserve account |  |  |  |  |  |  |  | $ 7,700,000 |  |  |  |  |  |  | $ 15,100,000 |  |  |  |  |  |  |  |  |  |  |
Debt service coverage ratio |  |  |  |  |  |  |  | 410.00% |  |  |  | 410.00% | 250.00% |  | 250.00% |  |  |  |  |  |  |  |  |  |  |
Total interest rate |  |  |  |  | 4.56% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt covenant, maximum loan to value percent |  |  |  |  |  |  |  | 22.30% |  |  |  | 22.30% |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of borrowing base |  |  |  |  |  |  |  | 35.00% |  |  |  | 35.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |
Kudu Credit Facility | Secured Debt | Forecast |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt service coverage ratio |  |  |  |  |  |  |  |  |  |  | 300.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Kudu Credit Facility | Secured Debt | Debt Covenant, Period 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt covenant, loan to value percent |  |  |  |  |  |  |  | 50.00% |  |  |  | 50.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |
Kudu Credit Facility | Secured Debt | Debt Covenant, Period 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt covenant, loan to value percent |  |  |  |  |  |  |  | 40.00% |  |  |  | 40.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |
Kudu Credit Facility | Secured Debt | Debt Covenant, Period 3 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt covenant, loan to value percent |  |  |  |  |  |  |  | 25.00% |  |  |  | 25.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |
Kudu Credit Facility | Secured Debt | Debt Covenant, Period 4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt covenant, loan to value percent |  |  |  |  |  |  |  | 15.00% |  |  |  | 15.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |
Kudu Credit Facility | Secured Debt | Debt Covenant, Period 5 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt covenant, loan to value percent |  |  |  |  |  |  |  | 0.00% |  |  |  | 0.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |
Kudu Credit Facility | Secured Debt | Secured Overnight Financing Rate (SOFR) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 0.26% | 0.26% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ark 2021 Subordinated Notes Tranche 3 | Subordinated Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face value |  |  | $ 70,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, period for interest rate increase |  |  | 10 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additional interest rate |  |  |  |  |  |  |  | 1.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Solvency capital requirement |  |  |  |  |  | 120.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt to capital requirement |  |  |  |  |  | 40.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amount borrowed |  |  |  |  |  |  |  | $ 70,000,000.0 |  |  |  |  |  |  | $ 70,000,000.0 |  |  |  |  |  |  |  |  |  |  |
Ark 2021 Subordinated Notes Tranche 3 | Subordinated Debt | London Interbank Offered Rate (LIBOR) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 6.10% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Citibank LOC Facility | Line of Credit | Letter of Credit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total commitment under revolving credit facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 125,000,000 |  |  |  |
Letters of credit outstanding |  |  |  |  |  |  |  | 99,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pledged collateral |  |  |  |  |  |  |  | 143,600,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lloyds LOC Facility | Line of Credit | Letter of Credit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total commitment under revolving credit facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 100,000,000 |  |  |  |  |  |
Letters of credit outstanding |  |  |  |  |  |  |  | 37,100,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pledged collateral |  |  |  |  |  |  |  | $ 68,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
HG Global Senior Notes | Senior Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face value |  | $ 150,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additional interest rate |  |  |  |  |  |  |  | 1.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amount borrowed |  |  |  |  |  |  |  | $ 150,000,000.0 |  |  |  |  |  |  | 150,000,000.0 |  |  |  |  |  |  |  |  |  |  |
Stated margin |  | 6.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Anniversary of funding date |  | 5 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Annual payments |  | $ 15,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest accrued multiplier |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 8 |  |  |  |  |
Interest reserve account, maximum |  |  |  |  |  |  |  | 29,300,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest reserve account |  |  |  |  |  |  |  | 29,300,000 |  |  |  |  |  |  | 29,300,000 |  |  |  |  |  |  |  |  |  |  |
HG Global Senior Notes | Senior Notes | Secured Overnight Financing Rate (SOFR) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  | 0.26% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Bamboo Credit Facility | Secured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face value | $ 110,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of notes |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amount borrowed |  |  |  |  |  |  |  | $ 110,000,000.0 |  |  |  |  |  |  | 0 |  |  |  |  |  |  |  |  |  |  |
Stated margin |  |  |  |  |  |  |  | 4.75% |  |  |  | 4.75% |  |  |  |  |  |  |  |  |  |  |  |  |  |
Annual payments | $ 1,100,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, term | 6 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, periodic payment, principal | $ 800,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total leverage ratio | 1.5 |  |  |  |  |  |  | 1.2 |  |  |  | 1.2 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Bamboo Credit Facility | Secured Debt | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stated margin | 4.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Bamboo Credit Facility | Secured Debt | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stated margin | 5.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total leverage ratio |  |  |  |  |  |  |  | 4.5 |  |  |  | 4.5 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Bamboo Credit Facility | Secured Debt | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total commitment under revolving credit facility | $ 10,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other Operations debt | Secured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amount borrowed |  |  |  |  |  |  |  | $ 21,500,000 |  |  |  |  |  |  | $ 22,400,000 |  |  |  |  |  |  |  |  |  |  |
Secured credit facilities | credit_facility |  |  |  |  |  |  |  | 4 |  |  |  | 4 |  |  |  |  |  |  |  |  |  |  |  |  |  |

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