FINANCIAL INSTRUMENTS AND RISK MANAGEMENT - Interest Rate Exposures (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Revolving credit facility
Risk management
Available amount	$ 1,000
Private placement debt
Risk management
Available amount	$ 25
Interest rate risk
Risk management
Percentage of increase in risk variable used for sensitivity analysis	1.00%
Percentage of decrease in risk variable used for sensitivity analysis	1.00%
Increase in annual net interest charge that would result from increased interest rate, per sensitivity analysis	$ 3	$ 5

- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

The increase (decrease) in annual net interest charge as a result of an increase in the relevant risk variable that was reasonably possible at the end of the reporting period.

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- Definition

The reasonably possible percentage of decrease in the relevant risk variable used to determine the financial impact in a sensitivity analysis.

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- Definition

The reasonably possible percentage of increase in the relevant risk variable used to determine the financial impact in a sensitivity analysis.

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