Stock-based compensation - Narrative (Details) - USD ($)					3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2025	Mar. 18, 2025	Mar. 08, 2024	Jan. 03, 2023	Sep. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Aggregate intrinsic value of exercisable service vesting-based stock options	$ 2,600,000				$ 2,600,000			$ 2,600,000
Intrinsic value of service vesting-based awards exercised					$ 200,000		$ 500,000	$ 200,000	$ 1,100,000
Service based-vesting options granted (in shares)					0			0
Weighted average remaining contractual life (year)								8 months 12 days
Stock based compensation expense					$ 5,895,000		4,134,000	$ 15,897,000	12,233,000
Vesting period (year)								4 years
Options
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized compensation costs for service vesting-based stock options	0				0			$ 0
Restricted Stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized compensation costs for service vesting-based stock options	$ 20,600,000				20,600,000			20,600,000
Fair value of PSA as of grant date					2,400,000		1,700,000	7,100,000	7,100,000
Stock based compensation expense					$ 2,800,000		2,700,000	$ 8,300,000	7,900,000
Period for recognition (year)								2 years 8 months 12 days
Granted (in shares)								470,824
Grant date fair value (in dollars per share)	$ 17.91				$ 17.91			$ 17.91		$ 16.00
Performance-based Restricted Stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized compensation costs for service vesting-based stock options	$ 900,000				$ 900,000			$ 900,000
Service based-vesting options granted (in shares)					0			0
Fair value of PSA as of grant date	1,900,000
Stock based compensation expense	(3,400,000)				$ 900,000		200,000	$ 2,200,000	700,000
Period for recognition (year)								2 months 12 days
Granted (in shares)			109,512
Grant date fair value (in dollars per share)			$ 17.36
Shares granted percentage						200.00%				100.00%
Incremental cost						$ 1,600,000
Performance-based Restricted Stock | Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total shareholder return attainment (percent)			0.00%
Performance-based Restricted Stock | Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total shareholder return attainment (percent)			200.00%
Market-based Restricted Stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized compensation costs for service vesting-based stock options	$ 7,700,000				7,700,000			$ 7,700,000
Stock based compensation expense			$ 300,000	$ 1,600,000	$ 2,200,000		1,200,000	$ 5,400,000	3,600,000
Period for recognition (year)								1 year 1 month 6 days
Granted (in shares)								451,801
Grant date fair value (in dollars per share)	$ 33.02				$ 33.02			$ 33.02		$ 25.69
Measurement date with a maturity period (year)								2 years
Dividend yield (percent)		0.00%	0.00%	0.00%				0.00%
Aggregate fair value of the market-based awards that vested					$ 0		$ 0	$ 11,800,000	$ 8,400,000
Market-based Restricted Stock | Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total shareholder return attainment (percent)		0.00%	0.00%	0.00%
Market-based Restricted Stock | Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total shareholder return attainment (percent)		200.00%	200.00%	200.00%