Income Taxes - Operating loss carryforwards (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Income Taxes
Tax expense	$ 0	$ 0
Increase in valuation allowance	19,500
Federal
Income Taxes
Operating loss carryforwards	245,500
Operating loss carryovers not subject to expiration	240,600
State
Income Taxes
Operating loss carryforwards	$ 217,500