Debt - Summary of Interest Expense Recognized (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Short Term Debt [Line Items]
Total interest expense recognized	$ 28,950	$ 30,045	$ 58,225	$ 60,398
Convertible Notes [Member]
Short Term Debt [Line Items]
Contractual interest coupon	2,618	2,618	5,235	5,235
Amortization of debt discount	4,457	4,186	8,845	8,308
Amortization of debt issuance costs	391	375	777	747
Total interest expense recognized	$ 7,466	$ 7,179	$ 14,857	$ 14,290

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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Amount of amortization expense attributable to debt issuance costs.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings, excluding amortization of debt discount (premium) and financing costs.

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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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