STOCK-BASED COMPENSATION - Plans (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) plan	Jun. 30, 2020 USD ($)
STOCK-BASED COMPENSATION
Stock-based compensation plans \| plan			2
Compensation expense on share-based plans	$ 17.3	$ 15.9	$ 35.7	$ 33.0
Excess tax benefit realized for tax deductions from non-qualified stock option exercises and disqualifying dispositions of incentive stock options	$ 2.7	$ 4.0	$ 4.1	$ 5.7

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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