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Deferred Finance Costs, Attributable to Liability Component

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Deferred Finance Costs, Equity Component

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Deferred tax asset on the equity component of deferred finance costs

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Deferred tax liability on the debt discount for conversion option

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Payments for Interest on Convertible Debt

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Payments for Repurchase of Convertible Debt

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Adjustment to additional paid in capital resulting from the recognition of convertible debt instruments as two separate components - a debt component and an equity component. This bifurcation may result in a basis difference associated with the liability component that represents a temporary difference for purposes of applying accounting for income taxes. The initial recognition of deferred taxes for the tax effect of that temporary difference is as an adjustment to additional paid in capital.

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Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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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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The price per share of the conversion feature embedded in the debt instrument.

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Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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

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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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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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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Maturity date of long-term debt, in CCYY-MM-DD format.

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The cash outflow to reacquire common stock during the period.

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The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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Price of a single share of a number of saleable stocks of a company.

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Long-term Debt - Convertible Senior Notes (Additional Notes) (Details) $ / shares in Units, $ in Thousands			3 Months Ended		9 Months Ended
	Aug. 14, 2020 USD ($) $ / shares	Sep. 11, 2018 USD ($) $ / shares	Sep. 30, 2020 USD ($) $ / shares	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) $ / shares	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Payments for repurchase of 2023 convertible notes					$ 170,720	$ 0
Loss on extinguishment of debt			$ 4,337	$ 0	$ 4,337	$ 0
Share price at closing (in dollars per share) \| $ / shares			$ 42.74		$ 42.74
Convertible debt \| 2023 Notes
Debt Instrument [Line Items]
Aggregated principal amount		$ 143,800
Interest rate stated, percentage		2.375%
Initial purchasers' discount and issuance costs		$ 4,400	$ (2,300)		$ (2,300)
Proceeds from debt, net of issuance costs		$ 139,400
Payments for repurchase of 2023 convertible notes			$ 172,000
Shares conversion rate		26.5957
Initial conversion price (in dollars per share) \| $ / shares	$ 46.62	$ 37.60
Maturity date			Sep. 15, 2023		Sep. 15, 2023
Principal			$ 12,510		$ 12,510		$ 143,750
Payment of interest			1,300
Loss on extinguishment of debt			$ 4,300
Convertible debt \| 2025 Notes
Debt Instrument [Line Items]
Aggregated principal amount	$ 230,000
Interest rate stated, percentage	1.25%
Initial purchasers' discount and issuance costs	$ 7,300
Proceeds from debt, net of issuance costs	222,700
Payments for repurchase of 2023 convertible notes	172,000
Cost of entering into hedges, net of warrants	26,700
Payments for working capital or other general corporate purposes	$ 24,000
Shares conversion rate	19.3538
Initial conversion price (in dollars per share) \| $ / shares	$ 51.67
Initial liability component of note	$ 181,100
Debt borrowing rate, percentage	6.30%
Debt discount for conversion option	$ 48,900
Deferred tax effect on conversion	12,600
Deferred financing cost	7,300
Deferred finance cost, attributable liability component	5,700
Deferred finance costs, equity component	1,600
Deferred tax asset, convertible debt equity component	$ 400
Maturity date			Aug. 01, 2025		Aug. 01, 2025
Principal			$ 230,000		$ 230,000		$ 0
Convertible debt, liability component \| 2023 Notes
Debt Instrument [Line Items]
Payments for repurchase of 2023 convertible notes			120,900
Convertible debt, equity component \| 2023 Notes
Debt Instrument [Line Items]
Payments for repurchase of 2023 convertible notes			$ 49,900
Debt borrowing rate, percentage			5.20%		5.20%