SHAREHOLDERS' EQUITY - SCHEDULE OF EARNINGS PER SHARE RECONCILIATION (Details) - USD ($) shares in Thousands, $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Payment Arrangement [Abstract]
Net income (loss) for diluted earnings per share	$ 409.4	$ (315.0)	$ 175.6
Shares:
Weighted average shares outstanding for basic earnings per share (in shares)	156,040	165,457	170,025
Effect of dilutive securities on weighted average shares:
Amounts related to employee benefit plans (in shares)	1,108	0	2,119
Weighted average shares outstanding for diluted earnings per share (in shares)	157,148	165,457	172,144

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities, and addition from assumption of issuance of common shares for dilutive potential common shares; of income (loss) available to common shareholders.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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