Face (par) amount of debt instrument at time of issuance.

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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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Face (par) amount of the original debt instrument that was repurchased.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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DEBT - 2.50% Convertible Senior Notes Due 2021 (Details) - USD ($) $ in Thousands	Sep. 01, 2021	Dec. 31, 2021	Dec. 31, 2020	Apr. 08, 2020	Feb. 19, 2020	Sep. 09, 2014
Debt Instrument [Line Items]
Principal amount outstanding		$ 73,493	$ 84,102
Convertible Senior Notes, 2.5% \| Convertible debt
Debt Instrument [Line Items]
Interest rate		2.50%				2.50%
Par value of debt						$ 345,000
Repurchased aggregate principal amount				$ 42,100	$ 102,500
Redemption of debt	$ 300
Principal amount outstanding		$ 0	$ 300