Fair value measurements - Derivative Instruments at Fair Value (Details) - USD ($)	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	$ 12,372,000	$ 27,072,000	$ 610,000	$ 698,000
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	48,367,000	67,067,000
Total
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	49,489,000	68,314,000
Public warrants | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	7,328,000	16,036,000
Public warrants | Total
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	7,328,000	16,036,000
Private warrants | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	5,043,000	11,036,000
Private warrants | Total
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	5,043,000	11,036,000
Senior secured term loan | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	35,996,000	39,995,000
Senior secured term loan | Total
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	37,118,000	41,242,000
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	7,328,000	16,036,000
Level 1 | Public warrants
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	7,328,000	16,036,000
Level 1 | Private warrants
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	0	0
Level 1 | Senior secured term loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	0	0
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	37,118,000	41,242,000
Level 2 | Public warrants
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	0	0
Level 2 | Private warrants
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	0	0
Level 2 | Senior secured term loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	37,118,000	41,242,000
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	5,043,000	11,036,000
Level 3 | Public warrants
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	0	0
Level 3 | Private warrants
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	5,043,000	11,036,000
Level 3 | Senior secured term loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	$ 0	$ 0