SHARE-BASED COMPENSATION - Summary of Share-Based Compensation Award Activity (Details) - $ / shares shares in Thousands	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Stock options
Stock options
Granted (in shares)	2,269	1,725
Weighted-average exercise price (in usd per share)	$ 24.74	$ 23.16
Weighted-average grant date fair value (in usd per share)	$ 6.60	$ 8.46
Time-based RSUs
RSUs
Granted (in shares)	3,084	2,895
Weighted-average grant date fair value (in usd per share)	$ 22.05	$ 23.93
TSR performance-based RSUs
RSUs
Granted (in shares)	425	454
Weighted-average grant date fair value (in usd per share)	$ 26.13	$ 34.53
ROTC performance-based RSUs
RSUs
Granted (in shares)	472	505
Weighted-average grant date fair value (in usd per share)	$ 27.05	$ 25.03

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

Net number of share options (or share units) granted during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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