Stock compensation and other employee benefit plans - Summary of outstanding restricted stock unit and restricted stock awards (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) $ / shares shares
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Granted, Shares	450,000
Vested, Shares	(2,415,526)
Nonvested, ending balance, Shares	457,045
Stock-based compensation cost not yet recognized | $	$ 233
Weighted-average remaining expense recognition period	1 year 14 days
Restricted stock units [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Nonvested, beginning balance, Shares	7,072,663
Granted, Shares	12,129,309
Vested, Shares	(3,841,815)
Forfeited, Shares	(3,469,021)
Nonvested, ending balance, Shares	11,891,136
Nonvested, beginning balance, Dollars per share | $ / shares	$ 4.73
Granted | $ / shares	1.54
Vested | $ / shares	3.92
Forfeited | $ / shares	4.28
Nonvested, ending balance, Dollars per share | $ / shares	$ 1.87
Stock-based compensation cost not yet recognized | $	$ 13,482
Weighted-average remaining expense recognition period	1 year 10 months 17 days
Restricted stock units [Member] | Service-Based Vesting [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Nonvested, ending balance, Shares	5,811,724
Nonvested, ending balance, Dollars per share | $ / shares	$ 3.15
Restricted stock units [Member] | Performance Conditions and Service-Based Vesting [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Nonvested, ending balance, Shares	779,412
Nonvested, ending balance, Dollars per share | $ / shares	$ 4.33
Restricted stock units [Member] | Market Conditions and Service-Based Vesting [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Nonvested, ending balance, Shares	5,300,000
Nonvested, ending balance, Dollars per share | $ / shares	$ 0.1