CONVERTIBLE NOTES - Schedule of Convertible Notes (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
2028 Notes
Long-term debt
Coupon interest rate	0.375%	0.375%
Principal Amount	$ 1,150,000	$ 1,150,000
Unamortized Debt Discount and Issuance Costs	(18,074)	(18,826)
Net Carrying Amount	1,131,926	1,131,174
2028 Notes \| Level 2 \| Fair Value
Long-term debt
Convertible notes, fair value	$ 1,032,125	$ 1,139,650
2027 Notes
Long-term debt
Coupon interest rate	0.375%	0.375%
Principal Amount	$ 747,500	$ 747,500
Unamortized Debt Discount and Issuance Costs	(11,137)	(11,691)
Net Carrying Amount	736,363	735,809
2027 Notes \| Level 2 \| Fair Value
Long-term debt
Convertible notes, fair value	$ 712,315	$ 771,794
2025 notes
Long-term debt
Coupon interest rate	1.00%	1.00%
Principal Amount	$ 315,005	$ 315,005
Unamortized Debt Discount and Issuance Costs	(1,614)	(1,756)
Net Carrying Amount	313,391	313,249
2025 notes \| Level 2 \| Fair Value
Long-term debt
Convertible notes, fair value	$ 377,833	$ 415,473

The amount as of balance sheet date of convertible notes payable including debt issuance costs and debt discounts.

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Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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