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Percentage of vesting of award under share-based payment arrangement.

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Number of shares remaining authorized to be purchased under share repurchase plan. Includes, but is not limited to, repurchase of stock and unit of ownership.

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Number of previously issued common shares repurchased by the issuing entity and held in treasury.

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CAPITAL STOCK - Narrative (Details) shares in Thousands, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025 USD ($) shares	Jun. 30, 2024 USD ($) shares	Jun. 30, 2025 USD ($) plan shares	Jun. 30, 2024 USD ($) plan shares	Dec. 31, 2024 USD ($) shares	Oct. 30, 2024 shares	Dec. 31, 2023 USD ($)	Dec. 12, 2023 shares
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Treasury stock, shares, share based compensation plan to be deliverable (in shares)			6,900
Treasury stock, share-based compensation plan settlement (in shares)	30	100	2,000	3,300
Share-based compensation cash settlement \| $	$ 0.0	$ 0.0	$ 156.0	$ 69.0
Treasury stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Treasury stock, common (in shares)	2,200		2,200		2,500
Common stock held by trustee for delivery under share-based compensation plans (in share) \| $	$ 202.2		$ 202.2		$ 92.9
2023 SBC
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Accrual for repurchase of stock under automatic share purchase plan \| $							$ 7.5
RSUs
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period			3 years
RSUs \| Share-Based Payment Arrangement, Tranche One
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting percentage			33.30%
RSUs \| Share-Based Payment Arrangement, Tranche Two
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting percentage			33.30%
RSUs \| Share-Based Payment Arrangement, Tranche Three
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting percentage			33.30%
Employee Stock Option
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period			4 years
Employee Stock Option \| Share-Based Payment Arrangement, Tranche One
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting percentage			25.00%
Employee Stock Option \| Share-Based Payment Arrangement, Tranche Two
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting percentage			25.00%
Employee Stock Option \| Share-Based Payment Arrangement, Tranche Three
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting percentage			25.00%
Employee Stock Option \| Share-Based Payment Arrangement, Tranche Four
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting percentage			25.00%
PSUs
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award performance period			3 years
PSUs \| Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based payment award, awards granted, percentage of target			0.00%
PSUs \| Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based payment award, awards granted, percentage of target			200.00%
Share-Based Payment Arrangement
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based compensation cash settlement \| $	$ 0.0	$ 0.0	$ 156.0	$ 69.0
2023 NCIB
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share repurchase program, authorized, number of shares (in shares)								11,800
Accrual for repurchase of stock under automatic share purchase plan \| $							$ 2.7
NCIB ASPP
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share repurchase program, number of effective plans \| plan			1	1
SBC ASPP
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share repurchase program, number of effective plans \| plan			1	2
2024 NCIB
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share repurchase program, authorized, number of shares (in shares)						8,600
Share repurchase program, remaining authorized, number of shares (in shares)	7,100		7,100