Business combination - Additional Information (Details) $ / shares in Units, shares in Millions, $ in Millions	Mar. 05, 2020 USD ($) $ / shares shares	Dec. 31, 2021 $ / shares	Dec. 31, 2020 $ / shares
Business Acquisition [Line Items]
Common stock, par value (in dollars per share) | $ / shares		$ 0.0001	$ 0.0001
Legal and professional fees | $	$ 4.7
Additional Paid-In-Capital, Reduction Of Proceeds
Business Acquisition [Line Items]
Legal and professional fees | $	4.1
General and administrative
Business Acquisition [Line Items]
Legal and professional fees | $	$ 0.6
ChaSerg
Business Acquisition [Line Items]
Stock redeemed, price per share (in usd per share) | $ / shares	$ 10.21
GDI | ChaSerg
Business Acquisition [Line Items]
Number of common stock shares acquired (in shares)	50.8
Common stock, par value (in dollars per share) | $ / shares	$ 0.0001
Number of warrants acquired (in shares)	11.3
Options, vested, outstanding and unexercised (in shares)	4.3
Earnout shares vested (in shares)	1.7
Options, vested, exchange ratio	248.00%
Options, nonvested, outstanding and unexercised (in shares)	0.4
Earnout shares, nonvested (in shares)	0.1
Options, nonvested, exchange ratio	248.00%
Stock redeemed (in shares)	0.1
GDI | ChaSerg | Adjustment
Business Acquisition [Line Items]
Exchange ratio	1.685
2017 Acquisition | Cost Of Revenue and Operating Expenses
Business Acquisition [Line Items]
Legal and professional fees | $	$ 3.4