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-Name Accounting Standards Codification
-Topic 260
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NET INCOME (LOSS) PER SHARE - Schedule Dilutive Shares Information (Details) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Aug. 13, 2019	Sep. 09, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total potentially dilutive common shares (in shares)	11,839	24,958	24,249	24,499
Stock options, awards and equivalents
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total potentially dilutive common shares (in shares)	10,500	7,027	7,826	6,568
2.50% Convertible Notes due 2021 \| Convertible debt
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Interest rate	2.50%		2.50%			2.50%
2.50% Convertible Notes due 2021 \| Convertible debt
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total potentially dilutive common shares (in shares)	234	17,931	2,685	17,931
5.0% Convertible Notes debt 2024 \| Convertible debt
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Interest rate	5.00%		5.00%		5.00%
5.0% Convertible Notes debt 2024 \| Convertible debt
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total potentially dilutive common shares (in shares)	1,105	0	13,738	0