Restricted stock units (Details) - $ / shares	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-Based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of restricted stock units created in connection with Exchange Offer		3,430,433
2017 LTIP
Share-Based Payment Arrangement, Option, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 18.40	$ 19.55	$ 20.27	$ 22.51
Granted, weighted average exercise price per share (in dollars per share)		4.69	9.30
Forfeited (in dollars per share)	$ 22.69	$ 21.94	$ 23.84
Restricted Stock Units \| 2017 LTIP
Share-Based Payment Arrangement, Option, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	21,314,660	19,975,943	3,597,775
Non-option equity instruments, outstanding (shares)	30,146,503	22,493,888	7,495,388	6,617,837
Vested (in shares)	(8,427,473)	(1,913,348)	(2,141,449)
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Forfeitures	(5,234,572)	(3,064,095)	(578,775)
Number of restricted stock units created in connection with Exchange Offer	3,430,433
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 3.12	$ 4.93	$ 12.41	$ 16.23
Granted, weighted average exercise price per share (in dollars per share)	2.51	4.15	8.00
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value	5.81	10.20	15.99
Forfeited (in dollars per share)	$ 3.87	$ 9.80	$ 15.48
Stock options \| 2017 LTIP
Share-Based Payment Arrangement, Option, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		640	7,888,472
Restricted Stock Award [Member] \| 2017 Amended LTIP \| Tranche One
Share-Based Payment Arrangement, Option, Exercise Price Range [Line Items]
Award vesting percentage	33.00%

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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Number of shares under non-option equity instrument agreements that were cancelled as a result of occurrence of a terminating event.

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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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Gross number of share options (or share units) granted during the period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage of vesting of award under share-based payment arrangement.

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Weighted average grant-date fair value of options vested.

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