Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Net increase or decrease in the carrying amount of the debt instrument for the period.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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

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The increase (decrease) during the reporting period in the account that represents the temporary difference that results from Income or Loss that is recognized for accounting purposes but not for tax purposes and vice versa.

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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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The increase (decrease) in stockholders' equity during the period.

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Recent Accounting Pronouncements - (Details) - 1.5% Convertible Unsecured Senior Notes - USD ($) $ in Thousands	Jan. 01, 2021	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Jan. 30, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stated interest rate		1.50%		1.50%
Convertible Debt
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Principal amount of the liability component		$ 157,369	$ 192,250
Effective interest rate percentage					6.00%
Stated interest rate		1.50%
Convertible Debt \| Forecast
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Effective interest rate percentage	2.00%
Convertible Debt \| Forecast \| Cumulative Effect, Period of Adoption, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Debt instrument, increase net	$ 12,200
Decrease in deferred income taxes	3,700
Net decrease, stockholder's equity	$ 8,500