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-Name Accounting Standards Codification
-Topic 260
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NET INCOME PER SHARE - Schedule Dilutive Shares Information (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Sep. 09, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total potentially dilutive common shares (in shares)	6,162	38,503
Stock options, awards and equivalents
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total potentially dilutive common shares (in shares)	6,145	7,144
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% 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	5,111
5.0% Convertible Notes debt 2024 \| Convertible notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Interest rate	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	26,248