Investments and fair value measurements - Level 3 Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Preferred Stock
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Exercise of redeemable convertible preferred stock warrants	$ (2,896)		$ (2,896)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	15,000	$ 0	10,000	$ 0
Purchases of strategic investments			5,000
Ending balance	12,104	0	12,104	0
Warrants
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	0	0	0	160
Exercise of redeemable convertible preferred stock warrants				(160)
Ending balance	0	0	0	0
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Purchases of strategic investments			0
Stock Appreciation Rights
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	419	791	818	268
Vesting and remeasurement of SARs	165	121	(234)	644
Amount reclassified from liability to equity upon exchange	(62)		(62)
Ending balance	$ 522	$ 912	522	$ 912
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Purchases of strategic investments			$ 0