Net gains (losses) from investment activities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Investments
Realized gain/(loss) on investments	$ (3,386)	$ 226
Unrealized gain/(loss) on investments	11,776	(8,449)
Asset Management
Investments
Realized gain/(loss) on investments	418	338
Unrealized gain/(loss) on investments	1,603	(1,869)
Credit releases (losses)	0	0
Net gains (losses) from investment activities	2,021	(1,531)
Asset Management \| Equity securities
Investments
Realized gain/(loss) on investments	418	338
Unrealized gain/(loss) on investments	262	(1,573)
Credit releases (losses)	0	0
Net gains (losses) from investment activities	680	(1,235)
Asset Management \| Derivatives
Investments
Realized gain/(loss) on investments	0	0
Unrealized gain/(loss) on investments	2	0
Credit releases (losses)	0	0
Net gains (losses) from investment activities	2	0
Asset Management \| Debt obligation
Investments
Realized gain/(loss) on investments	0	0
Unrealized gain/(loss) on investments	1,339	(296)
Credit releases (losses)	0	0
Net gains (losses) from investment activities	1,339	(296)
Insurance Solutions \| Consolidated Entity, Excluding Consolidated VIE
Investments
Realized gain/(loss) on investments	(3,423)	(219)
Unrealized gain/(loss) on investments	13,564	(3,761)
Credit releases (losses)	(3,924)	(4,231)
Net gains (losses) from investment activities	6,217	(8,211)
Insurance Solutions \| Variable Interest Entity, Primary Beneficiary
Investments
Realized gain/(loss) on investments	(386)	107
Unrealized gain/(loss) on investments	(2,015)	(3,177)
Credit releases (losses)	0	0
Net gains (losses) from investment activities	(2,401)	(3,070)
Insurance Solutions \| Consolidated Balance Including Variable Interest Entity
Investments
Realized gain/(loss) on investments	(3,809)	(112)
Unrealized gain/(loss) on investments	11,549	(6,938)
Credit releases (losses)	(3,924)	(4,231)
Net gains (losses) from investment activities	3,816	(11,281)
Insurance Solutions \| Equity securities
Investments
Realized gain/(loss) on investments	(246)	(3)
Unrealized gain/(loss) on investments	2,330	785
Credit releases (losses)	0	0
Net gains (losses) from investment activities	2,084	782
Insurance Solutions \| U.S. state, territories and municipalities
Investments
Realized gain/(loss) on investments	(4)	(5)
Unrealized gain/(loss) on investments	51	(10)
Credit releases (losses)	0	0
Net gains (losses) from investment activities	47	(15)
Insurance Solutions \| Other government and agency
Investments
Realized gain/(loss) on investments	0	0
Unrealized gain/(loss) on investments	115	(18)
Credit releases (losses)	0	0
Net gains (losses) from investment activities	115	(18)
Insurance Solutions \| Corporate
Investments
Realized gain/(loss) on investments	(1,773)	(165)
Unrealized gain/(loss) on investments	5,023	(3,710)
Credit releases (losses)	0	0
Net gains (losses) from investment activities	3,250	(3,875)
Insurance Solutions \| Asset and mortgage-backed securities
Investments
Realized gain/(loss) on investments	(641)	(158)
Unrealized gain/(loss) on investments	117	4,041
Credit releases (losses)	0	0
Net gains (losses) from investment activities	(524)	3,883
Insurance Solutions \| Corporate loans
Investments
Realized gain/(loss) on investments	(4)	110
Unrealized gain/(loss) on investments	1,853	(594)
Credit releases (losses)	0	0
Net gains (losses) from investment activities	1,849	(484)
Insurance Solutions \| Mortgage loans
Investments
Realized gain/(loss) on investments	0	0
Unrealized gain/(loss) on investments	0	0
Credit releases (losses)	(4,057)	(4,693)
Net gains (losses) from investment activities	(4,057)	(4,693)
Insurance Solutions \| Other
Investments
Realized gain/(loss) on investments	(755)	2
Unrealized gain/(loss) on investments	4,075	(4,255)
Credit releases (losses)	133	462
Net gains (losses) from investment activities	$ 3,453	$ (3,791)

Amount of realized and unrealized gain (loss) on investment.

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of realized gain (loss) on investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of unrealized gain (loss) on investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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