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

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-Publisher FASB
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt discount.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
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Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

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- Details

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Long-Term Debt - Carrying Value of 2024 Notes and 2020 Notes (Details) - Convertible Debt - USD ($)	Jun. 30, 2020	Dec. 31, 2019	Jun. 03, 2019	Mar. 11, 2015
Debt Instrument [Line Items]
Principal	$ 400,000,000	$ 494,909,000
Unamortized interest discount		(65,393,000)
Deferred financing costs		(5,859,000)
Net carrying amount of 2024 and 2020 Notes	336,544,000	423,657,000
Convertible Notes 2024
Debt Instrument [Line Items]
Principal	400,000,000	400,000,000	$ 400,000,000.0
Unamortized interest discount	(58,246,000)	(64,724,000)
Deferred financing costs	(5,210,000)	(5,789,000)
Net carrying amount of 2024 and 2020 Notes	$ 336,544,000	329,487,000
Convertible Notes 2020
Debt Instrument [Line Items]
Principal		94,909,000		$ 316,000,000.0
Unamortized interest discount		(669,000)
Deferred financing costs		(70,000)
Net carrying amount of 2024 and 2020 Notes		$ 94,170,000