Stock-based compensation - Summary of Deferred Share Units Plan (Details) - DSUs - shares	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] (in shares)
Outstanding, January 1 (in shares)	899,818	744,530
Granted (in shares)	71,082	85,750
PDSUs converted into DSUs (in shares)	14,079	81,533
Issued in lieu of dividends (in shares)	6,253	5,685
Settled (in shares)	(82,624)	(15,935)
Forfeited (in shares)	(5,554)	(1,745)
Outstanding, December 31 (in shares)	903,054	899,818