Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund.

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Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3).

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Amount, after allowance for credit loss, of financing receivable, classified as noncurrent.

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Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

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Amount before tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount, before tax and after adjustments, of gain (loss) from increase (decrease) in value of excluded component of derivative designated and qualifying as hedge. Adjustments include, but are not limited to, reclassifications for sale and settlement, and amounts recognized under systematic and rational method.

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Amount, before tax and adjustments, of gain (loss) from increase (decrease) in value of excluded component of derivative designated and qualifying as hedge. Adjustments include, but are not limited to, reclassifications for sale and settlement, and amounts recognized under systematic and rational method.

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The aggregate value of all restricted investments.

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RISK MANAGEMENT AND FINANCIAL INSTRUMENTS - Other Financial Instruments (Details) - CAD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Fair Value of Other Financial Instruments
FMVA investments	$ 52		$ 52		$ 52
Restricted long-term investments	543		543		630
Long-term debt, carrying value	77,500		77,500		74,400
Long-term debt	73,100		73,100		82,000
Net investment hedges
Fair Value of Other Financial Instruments
Unrealized foreign exchange gain (loss) on translation of United States dollar denominated debt			(257)	$ 251
Unrealized gain (loss) on change in fair value of outstanding forward exchange forward contracts			0	0
Unrealized gain (loss) associated with the settlement of outstanding forward exchange forward contracts			0	0
Level 1
Fair Value of Other Financial Instruments
Restricted long-term investments	194		194		217
Level 2
Fair Value of Other Financial Instruments
Restricted long-term investments	349		349		413
Fair value of investments	322		322		304
Unrealized gain (loss) on lnvestments	(19)	$ 4	(27)	3
Fair Value
Fair Value of Other Financial Instruments
Unrealized holding gains (losses)	(71)	$ 20	(131)	$ (25)
Fair value note receivable	840		840		954
Carrying value
Fair Value of Other Financial Instruments
Non-current notes receivable	$ 840		$ 840		$ 954