Debt - Schedule of Convertible Senior Notes (Details) - 2025 Notes - Convertible Debt - USD ($)	Jun. 30, 2019	Dec. 31, 2018	May 31, 2018
Liability component:
Principal	$ 1,150,000,000	$ 1,150,000,000	$ 1,150,000,000.0
Less: debt discount and issuance costs, net of amortization	(256,809,000)	(275,920,000)
Net carrying amount	893,191,000	874,080,000
Equity component:	$ 285,225,000	$ 285,225,000

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

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- Definition

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

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Amount of unamortized debt discount (premium) and debt issuance costs.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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