Investments in debt and equity securities - Schedule of Gross Unrealized Gains and Losses (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]
Gains	$ 4,391	$ 5,839
Losses	6,707	5,895
Municipal
Debt Securities, Available-for-sale [Line Items]
Gains	4	5
Losses	8	23
Corporate
Debt Securities, Available-for-sale [Line Items]
Gains	648	1,646
Losses	3,370	2,596
Foreign
Debt Securities, Available-for-sale [Line Items]
Gains	3,651	3,645
Losses	2,659	3,149
U.S. Treasury Bonds
Debt Securities, Available-for-sale [Line Items]
Gains	88	543
Losses	$ 670	$ 127

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.

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+ Details