Income taxes - Cash for income taxes paid (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Cash for income taxes paid
Federal	$ 36
Income Taxes Paid, Net, Total	73	$ 2,331
California
Cash for income taxes paid
State	7
Pennsylvania
Cash for income taxes paid
State	2
Tennessee
Cash for income taxes paid
State	12
Texas
Cash for income taxes paid
State	10
All other state
Cash for income taxes paid
State	$ 6

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Amount, after income tax refund received, of cash paid to federal (national) tax jurisdiction for tax on income.

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Amount, after refund, of cash paid to foreign, federal, state, and local jurisdictions as income tax.

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