CAPITAL STOCK - Schedule of Common Shares Purchases (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Share-Based Payment Arrangement [Abstract]
Aggregate cost (including transaction fees and excluding share buyback taxes) of Common Shares repurchased for cancellation	$ 20.0	$ 75.0
Number of Common Shares repurchased for cancellation (in shares)	0.1	0.6
Weighted average price per share for repurchases (in dollars per share)	$ 273.60	$ 114.46
Aggregate cost (including transaction fees) of Common Shares repurchased for delivery under SBC plans	$ 0.0	$ 221.6
Number of Common Shares repurchased for delivery under SBC plans (in shares)	0.0	1.7

Payments for Repurchase of Common Stock, Excluding Share Buyback Taxes

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- Definition

Payments For Repurchase Of Treasury Stock For Share-Based Compensation Plans

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- Definition

Treasury Stock, Shares, Acquired for Share Based Compensation Plans

+ References

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

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