Fair value measurements - Schedule of Available-for-Sale Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025	Jun. 30, 2025
Debt Securities, Available-for-sale [Abstract]
Cost	$ 12,405	$ 12,531	$ 11,819
Gross Unrealized Gains	34	61	77
Gross Unrealized Losses	266	204	262
Fair Value	12,173	12,388	11,634
Mortgage-backed securities
Debt Securities, Available-for-sale [Abstract]
Cost	8,638	8,539	8,403
Gross Unrealized Gains	1	28	24
Gross Unrealized Losses	261	204	260
Fair Value	8,378	8,363	8,167
U.S. Treasury securities
Debt Securities, Available-for-sale [Abstract]
Cost	3,767	3,992	3,416
Gross Unrealized Gains	33	33	53
Gross Unrealized Losses	5	0	2
Fair Value	$ 3,795	$ 4,025	$ 3,467

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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+ Details

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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