Long-Term Debt - Schedule of Convertible Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Unamortized Issuance Costs	$ (14,493)	$ (8,990)
Long-term debt, net of issuance costs	2,563,198	2,754,443
Convertible Senior Notes Due 2026
Debt Instrument [Line Items]
Long-term debt, net of issuance costs	229,580	$ 0
Convertible Senior Notes Due 2026 \| Convertible Debt
Debt Instrument [Line Items]
Principal	345,000
Unamortized Discount	(108,558)
Unamortized Issuance Costs	(6,862)
Long-term debt, net of issuance costs	229,580
Equity Component, net of Purchase Discounts and Issuance Costs	$ 78,307

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 carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

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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, after accumulated amortization, of debt discount.

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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 remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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