segment information - Income before income taxes (Details) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Income before income taxes
Operating revenues external	$ 14,658	$ 14,368
Goods and services purchased	6,070	6,368
Employee benefits expense	3,034	2,896
EBITDA	5,554	5,104
Depreciation	1,929	1,669
Amortization	648	598
Operating income	2,977	2,837
Financing costs	733	661
INCOME BEFORE INCOME TAXES	$ 2,244	$ 2,176

The amount of amortisation of intangible assets other than goodwill. [Refer: Depreciation and amortisation expense; Intangible assets other than goodwill]

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The amount of depreciation of property, plant and equipment. [Refer: Depreciation and amortisation expense; Property, plant and equipment]

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The profit (loss) before tax expense or income. [Refer: Profit (loss)]

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Expiry date 2020-01-01: The income arising in the course of an entity's ordinary activities. Income is increases in economic benefits during the accounting period in the form of inflows or enhancements of assets or decreases of liabilities that result in an increase in equity, other than those relating to contributions from equity participants. Effective 2020-01-01: The income arising in the course of an entity's ordinary activities. Income is increases in assets, or decreases in liabilities, that result in increases in equity, other than those relating to contributions from holders of equity claims.

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