NET EARNINGS (LOSS) PER SHARE AND SHARE REPURCHASES - Dilutive Potential Common Shares (Details) - shares shares in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Earnings Per Share Basic And Diluted [Line Items]
Basic	746,896	745,486	746,715	746,041
Dilutive potential common shares	88	746	355	0
Diluted	746,984	746,232	747,070	746,041
Stock options
Earnings Per Share Basic And Diluted [Line Items]
Dilutive potential common shares	0	354	169	0
Restricted stock units
Earnings Per Share Basic And Diluted [Line Items]
Dilutive potential common shares	38	334	161	0
Performance share units
Earnings Per Share Basic And Diluted [Line Items]
Dilutive potential common shares	50	58	25	0

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=121326447&loc=d3e1707-109256

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
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-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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Earnings per share basic and diluted.

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