EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Numerator:
Net earnings	$ 10.9	$ 18.0
Denominator: (shares in thousands)
Denominator for basic earnings per share - weighted-average shares (in shares)	48,973,000	48,775,000
Potentially dilutive shares resulting from stock plans (in shares)	735,000	415,000
Denominator for diluted earnings per share - weighted-average shares (in shares)	49,708,000	49,190,000
Anti-dilutive equity awards not included in weighted-average common shares—diluted (in shares)	110,000	110,000
Net earnings per share:
Basic (in dollars per share)	$ 0.22	$ 0.37
Diluted (in dollars per share)	$ 0.22	$ 0.37

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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