Income Taxes - Components of deferred tax assets (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Deferred tax assets:
Investment in partnership	$ 119,033	$ 115,667
Tax credit carryforwards	1,537	513
Net operating loss carryforwards	13,794	6,048
Total deferred tax assets	134,364	122,228
Less valuation allowance	(134,364)	(122,228)
Deferred tax assets, net of valuation allowance	0	0
Net deferred tax liabilities	0	0
Federal net operating losses	50,300	22,000
Federal tax credits	1,500	500
unrecognized tax benefits	$ 0	$ 0