RISK MANAGEMENT AND FINANCIAL INSTRUMENTS - Fair Value of Non-Derivative Financial Instruments (Details) $ in Millions, $ in Billions	12 Months Ended
Dec. 31, 2022 CAD ($)	Dec. 31, 2021 CAD ($)	Dec. 31, 2022 USD ($)
Carrying and fair values of non-derivative financial instruments
Long-term debt, including current portion	$ (41,706)	$ (38,756)
Junior subordinated notes (Note 21)	(10,495)	(8,939)
Long-term debt	1,600	0
Interest rate swap agreements
Carrying and fair values of non-derivative financial instruments
Hedged items	64	0
Long-term debt hedged		0	$ 1.6
Level II \| Carrying Amount
Carrying and fair values of non-derivative financial instruments
Long-term debt, including current portion	(41,543)	(38,661)
Junior subordinated notes (Note 21)	(10,495)	(8,939)
Total liabilities	(52,038)	(47,600)
Level II \| Fair Value
Carrying and fair values of non-derivative financial instruments
Long-term debt, including current portion	(39,505)	(45,615)
Junior subordinated notes (Note 21)	(9,415)	(9,236)
Total liabilities	$ (48,920)	$ (54,851)

Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount of hedged item in hedging relationship. Excludes hedged asset or liability.

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Carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments, excluding current portion.

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Fair value of financial and nonfinancial obligations.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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