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Amount of cash outflow to satisfy grantee's tax withholding obligation for award under share-based payment arrangement.

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Number of shares issued for nonredeemable preferred shares and preferred shares redeemable solely at option of issuer. Includes, but is not limited to, preferred shares issued, repurchased, and held as treasury shares. Excludes preferred shares classified as debt.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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

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CAPITAL STOCK - Narrative (Details) $ in Millions	1 Months Ended	12 Months Ended
CAPITAL STOCK - Narrative (Details) $ in Millions	Oct. 31, 2023 USD ($)	Dec. 31, 2025 USD ($) vote shares	Dec. 31, 2024 USD ($) shares	Dec. 31, 2023 USD ($) shares	Oct. 29, 2025 shares	Oct. 30, 2024 shares	Dec. 12, 2023 shares
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Preferred stock, votes \| vote		1
Preferred stock, shares issued (in shares)		0
SBC cash settlement \| $		$ 224.8	$ 84.6	$ 66.7
Capital stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Cancelled under NCIB (in shares)		1,300,000	3,200,000
RSU and PSU
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
SBC cash settlement \| $		$ 224.8	$ 84.6	7.7
Share-based payment arrangement, cash used to settle award \| $				$ 49.8
PSUs
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based payment award, awards granted, percentage of target		100.00%
Share-based compensation arrangement, fair value assumptions, premium percentage		122.00%	120.00%	118.00%
Share-based compensation arrangement, equity instruments other than options, vested in period, fair value \| $		$ 266.8	$ 136.2	$ 39.2
Share-based compensation award, shares outstanding (in shares)		2,200,000	3,100,000
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%
RSUs
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based compensation arrangement, equity instruments other than options, vested in period, fair value \| $		$ 321.0	$ 90.3	41.0
Share-based compensation award, shares outstanding (in shares)		800,000	2,100,000
RSUs \| Director
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based compensation award, shares outstanding (in shares)		10,000.00	30,000.00
Deferred Stock Unit (DSUs)
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based compensation arrangement, equity instruments other than options, vested in period, fair value \| $		$ 26.7	$ 16.9	19.2
Share-based compensation award, shares outstanding (in shares)		400,000	700,000
Deferred Stock Unit (DSUs) \| Onex Corporation
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based payment arrangement, cash used to settle award \| $	$ 9.2
2022 NCIB
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share repurchase program, authorized, number of shares (in shares)							11,800,000
2023 NCIB
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share repurchase program, authorized, number of shares (in shares)						8,600,000
Accrual for repurchase of stock under automatic share purchase plan \| $				$ 2.7
Contractual maximum quantity for cancellation, share amount (in shares)				100,000
2023 NCIB \| Capital stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Cancelled under NCIB (in shares)				2,700,000
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
Contractual maximum quantity for cancellation, share amount (in shares)				300,000
2024 NCIB
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share repurchase program, authorized, number of shares (in shares)					5,700,000
Share repurchase program, remaining authorized, number of shares (in shares)		5,600,000