Income taxes (Tables)

12 Months Ended

Dec. 31, 2024

Major components of tax expense (income) [abstract]

Expense composition

Years Ended December 31 (millions)	2024		2023		2022
Current income tax expense (recovery)
For current reporting period	$	67	$	67	$	96
Pillar Two global minimum tax	2		—		—
Adjustments recognized in the current period for income tax of prior periods	(7)		(5)		1
	62		62		97
Deferred income tax (recovery)
Arising from the origination and reversal of temporary differences	(52)		(55)		(31)
Arising from the write-down of a deferred tax asset	24		—		—
Adjustments recognized in the current period for income tax of prior periods	5		(2)		1
	(23)		(57)		(30)
	$	39	$	5	$	67

Rate reconciliations

Our income tax expense and effective income tax rate differ from that calculated by applying the applicable statutory rates for the following reasons:

Years Ended December 31 (millions, except percentages)	2024				2023				2022
Income taxes computed at applicable statutory income tax rates	$	(17)	76.2	%	$	5	7.8	%	$	57	22.7	%
Non-deductible (taxable) items	6				—				9
Withholding and other taxes	23				18				23
Losses not recognized	19				1				7
Foreign tax differential	—				(12)				(30)
Adjustments recognized in the current period for income tax of prior periods	(2)				(7)				2
Pillar Two global minimum tax	2				—				—
Reversal of previously recognized deferred tax asset	9				—				—
Other	(1)				—				(1)
Income tax expense	$	39	(177.3)	%	$	5	8.5	%	$	67	26.8	%

Temporary differences

(millions)	Property, plant and equipment and intangible assets		Net pension and share- based compensation amounts		Debt and equity issue costs		Provisions and other		Non-capital loss carried forward		Leases		Net deferred income tax asset (liability)
As at January 1, 2023	$	(276)	$	1	$	6	$	7	$	10	$	2	$	(250)
Acquired during the year & other	(83)		—		—		2		14		—		(67)
Deferred income tax (expense) recovery recognized in:
Net income	35		2		(2)		4		16		2		57
Other comprehensive income	—		—		—		4		(2)		—		2
Foreign currency translation	(3)		—		—		—		—		—		(3)
As at December 31, 2023	$	(327)	$	3	$	4	$	17	$	38	$	4	$	(261)
Deferred income tax (expense) recovery recognized in:
Net income (loss)	29		5		(2)		(1)		(8)		—		23
Other comprehensive income (loss)	—		—		—		—		(1)		—		(1)
Foreign currency translation	5		—		—		—		—		—		5
Share capital	—		—		—		—		(9)		—		(9)
Other	(2)		—		(1)		2		(1)		1		(1)
As at December 31, 2024	$	(295)	$	8	$	1	$	18	$	19	$	5	$	(244)