RECENT ACCOUNTING PRONOUNCEMENTS - Cumulative Effect of ASU Adoption (Details) - USD ($) $ in Thousands	Apr. 01, 2022	Dec. 31, 2021
Liabilities
Convertible debt, current	$ 37,518	$ 36,824
Convertible debt, non-current	113,324	98,941
Mezzanine equity
Convertible debt		883
Equity
Additional paid-in capital	2,362,873	2,387,039
Accumulated deficit	$ (2,073,288)	(2,087,957)
Cumulative Effect, Period of Adoption, Adjustment \| ASU 2020-06
Liabilities
Convertible debt, current		626
Convertible debt, non-current		14,167
Mezzanine equity
Convertible debt		(883)
Equity
Additional paid-in capital		(32,249)
Accumulated deficit		18,339
Cumulative Effect, Period of Adoption, Adjusted Balance
Liabilities
Convertible debt, current		37,450
Convertible debt, non-current		113,108
Mezzanine equity
Convertible debt		0
Equity
Additional paid-in capital		2,354,790
Accumulated deficit		$ (2,069,618)

Value received from shareholders in common stock-related transactions that are in excess of par value or stated value and amounts received from other stock-related transactions. Includes only common stock transactions (excludes preferred stock transactions). May be called contributed capital, capital in excess of par, capital surplus, or paid-in capital.

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The portion of the carrying value of long-term convertible debt as of the balance sheet date that is scheduled to be repaid within one year or in the normal operating cycle if longer. Convertible debt is a financial instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Carrying amount, attributable to parent, of an entity's issued and outstanding stock which is not included within permanent equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. Includes stock with a put option held by an ESOP and stock redeemable by a holder only in the event of a change in control of the issuer.

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