STOCK-BASED COMPENSATION - Additional Information (Details) shares in Millions, $ in Millions	6 Months Ended
Jun. 30, 2019 USD ($) shares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Unrecognized stock-based compensation expense \| $	$ 99.5
Weighted-average period of recognition of unrecognized stock-based compensation expense (in years)	2 years 2 months 12 days
Shares issued (in shares) \| shares	0.8

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Number of share options (or share units) exercised during the current period.

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