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FINANCING ARRANGEMENTS - Schedule of Interest Costs on Convertible Debt (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Apr. 30, 2021	Apr. 04, 2016
Debt Instrument [Line Items]
Amortization of debt discount	$ 1,601	$ 14,621	$ 13,200
Senior Notes \| 3.25% Convertible Senior Notes due 2022
Debt Instrument [Line Items]
Contractual interest	3,024	8,128	8,128
Amortization of debt discount	451	14,621	13,200
Total	3,475	$ 22,749	$ 21,328
Debt stated interest rate					3.25%
Senior Notes \| 1.125% Convertible Senior Notes Due 2026
Debt Instrument [Line Items]
Contractual interest	2,001
Amortization of debt discount	1,150
Total	$ 3,151
Debt stated interest rate				1.125%