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-Name Accounting Standards Codification
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NET INCOME (LOSS) PER SHARE - Schedule Dilutive Shares Information (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 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)	12,270	39,293	20,825	29,484
Stock options, awards and equivalents
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total potentially dilutive common shares (in shares)	12,253	6,718	9,911	6,618
2.50% Convertible Notes due 2021 \| Convertible notes
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 notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total potentially dilutive common shares (in shares)	17	12,313	1,789	16,038
5.0% Convertible Notes debt 2024 \| Convertible notes
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 notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total potentially dilutive common shares (in shares)	0	20,262	9,125	6,828