Commitments and contingencies (Details) |
6 Months Ended |
|---|---|
|
Jun. 30, 2026
USD ($)
| |
| Commitments and contingencies | |
| Estimated litigation liability | $ 5,300,000 |
| Interest rate description litigation | plus legal interest that accrued at 12% per annum from August 13, 2008 to June 30, 2013, and thereafter accrued and continues to accrue legal interest at 6% per annum |
| Litigation settlement expense | $ 650,000 |