Property, plant and equipment - Schedule of Property, Plant and Equipment (Details) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Changes in property, plant and equipment, including right-of-use assets [abstract]
Beginning balance	$ 30,352	$ 29,256
Ending balance	30,001	30,352
Cost
Changes in property, plant and equipment, including right-of-use assets [abstract]
Beginning balance	86,836	83,612
Additions	4,629	5,961
Business acquisitions/(business disposition)	266	(195)
Transfers	(1,279)	(870)
Retirements and disposals	1,724	1,612
Impairment losses recognized in earnings	(180)	(42)
Reclassified to assets held for sale	(11)	(18)
Ending balance	88,537	86,836
Accumulated depreciation
Changes in property, plant and equipment, including right-of-use assets [abstract]
Beginning balance	(56,484)	(54,356)
Business acquisitions/(business disposition)		(18)
Transfers		25
Retirements and disposals	(1,661)	(1,545)
Reclassified to assets held for sale		(6)
Depreciation	3,758	3,745
Other	(45)	(73)
Ending balance	(58,536)	(56,484)
Network infrastructure and equipment
Changes in property, plant and equipment, including right-of-use assets [abstract]
Beginning balance	23,750	22,639
Ending balance	23,470	23,750
Network infrastructure and equipment \| Cost
Changes in property, plant and equipment, including right-of-use assets [abstract]
Beginning balance	74,676	71,875
Additions	2,092	2,990
Business acquisitions/(business disposition)	72	8
Transfers	881	1,368
Retirements and disposals	1,484	1,557
Impairment losses recognized in earnings	(85)	0
Reclassified to assets held for sale	(1)	(8)
Ending balance	76,151	74,676
Network infrastructure and equipment \| Accumulated depreciation
Changes in property, plant and equipment, including right-of-use assets [abstract]
Beginning balance	(50,926)	(49,236)
Business acquisitions/(business disposition)		(1)
Transfers		23
Retirements and disposals	(1,447)	(1,508)
Reclassified to assets held for sale		(6)
Depreciation	3,245	3,254
Other	(43)	(72)
Ending balance	(52,681)	(50,926)
Land and buildings
Changes in property, plant and equipment, including right-of-use assets [abstract]
Beginning balance	4,247	4,019
Ending balance	4,306	4,247
Land and buildings \| Cost
Changes in property, plant and equipment, including right-of-use assets [abstract]
Beginning balance	9,805	9,139
Additions	430	795
Business acquisitions/(business disposition)	184	(103)
Transfers	79	79
Retirements and disposals	232	53
Impairment losses recognized in earnings	(95)	(42)
Reclassified to assets held for sale	(10)	(10)
Ending balance	10,161	9,805
Land and buildings \| Accumulated depreciation
Changes in property, plant and equipment, including right-of-use assets [abstract]
Beginning balance	(5,558)	(5,120)
Business acquisitions/(business disposition)		(17)
Transfers		2
Retirements and disposals	(214)	(37)
Reclassified to assets held for sale		0
Depreciation	513	491
Other	(2)	(1)
Ending balance	(5,855)	(5,558)
Assets under construction
Changes in property, plant and equipment, including right-of-use assets [abstract]
Beginning balance	2,355	2,598
Ending balance	2,225	2,355
Assets under construction \| Cost
Changes in property, plant and equipment, including right-of-use assets [abstract]
Beginning balance	2,355	2,598
Additions	2,107	2,176
Business acquisitions/(business disposition)	10	(100)
Transfers	(2,239)	(2,317)
Retirements and disposals	8	2
Impairment losses recognized in earnings	0	0
Reclassified to assets held for sale	0	0
Ending balance	2,225	2,355
Assets under construction \| Accumulated depreciation
Changes in property, plant and equipment, including right-of-use assets [abstract]
Beginning balance	0	0
Business acquisitions/(business disposition)		0
Transfers		0
Retirements and disposals	0	0
Reclassified to assets held for sale		0
Depreciation	0	0
Other	0	0
Ending balance	$ 0	$ 0

Acquisitions through business combinations (disposals), property, plant and equipment including right-of-use assets

No definition available.

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- Definition

The amount of additions to property, plant and equipment including right-of-use assets other than those acquired through business combinations. [Refer: Total for all business combinations [member]; Property, plant and equipment including right-of-use assets]

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The decrease in property, plant and equipment including right-of-use assets through classification as held for sale or inclusion in a disposal group classified as held for sale. [Refer: Disposal groups classified as held for sale [member]; Property, plant and equipment including right-of-use assets; Disposal groups classified as held for sale [member]]

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The amount of depreciation of property, plant and equipment including right-of-use assets. [Refer: Depreciation and amortisation expense; Property, plant and equipment including right-of-use assets]

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The decrease in property, plant and equipment including right-of-use assets resulting from disposals and retirements. [Refer: Property, plant and equipment including right-of-use assets]

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The amount of impairment loss recognised in profit or loss for property, plant and equipment including right-of-use assets. [Refer: Impairment loss recognised in profit or loss; Property, plant and equipment including right-of-use assets]

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The increase (decrease) in property, plant and equipment including right-of-use assets resulting from changes that the entity does not separately disclose in the same statement or note. [Refer: Property, plant and equipment including right-of-use assets]

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The increase (decrease) in property, plant and equipment including right-of-use assets resulting from transfers. [Refer: Property, plant and equipment including right-of-use assets]

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- Definition

The amount of property, plant and equipment including right-of-use assets whose underlying assets would be presented as property, plant and equipment if they were owned. [Refer: Property, plant and equipment; Right-of-use assets]

+ References

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