Debt - Convertible and Exchangeable Senior Notes (Details) $ / shares in Units, shares in Thousands	3 Months Ended
Mar. 31, 2020 USD ($) d $ / shares shares	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Convertible and exchangeable senior notes, outstanding principal	$ 616,105,000	$ 616,105,000
Convertible and Exchangeable Senior Notes
Debt Instrument [Line Items]
Redemption price, percentage of principal amount (percentage)	100.00%
Threshold percentage of stock price trigger (percentage)	130.00%
Threshold trading days \| d	20
Threshold consecutive trading days \| d	30
Convertible and Exchangeable Senior Notes \| 5.00% Convertible Notes
Debt Instrument [Line Items]
Interest Rate (percentage)	5.00%
Conversion or Exchange Price (in USD per share of common stock) \| $ / shares	$ 15.76
Conversion or Exchange Ratio (In shares per $1,000)	63.4700
Conversion or Exchange Shares (in shares) \| shares	12,694
Convertible and exchangeable senior notes, outstanding principal	$ 200,000,000	200,000,000
Convertible and Exchangeable Senior Notes \| 3.875% Convertible Notes
Debt Instrument [Line Items]
Interest Rate (percentage)	3.875%
Conversion or Exchange Price (in USD per share of common stock) \| $ / shares	$ 16.57
Conversion or Exchange Ratio (In shares per $1,000)	60.3431
Conversion or Exchange Shares (in shares) \| shares	24,288
Convertible and exchangeable senior notes, outstanding principal	$ 402,500,000	402,500,000
Convertible and Exchangeable Senior Notes \| 5.375% Exchangeable Notes
Debt Instrument [Line Items]
Interest Rate (percentage)	5.375%
Conversion or Exchange Price (in USD per share of common stock) \| $ / shares	$ 12.04
Conversion or Exchange Ratio (In shares per $1,000)	83.0837
Conversion or Exchange Shares (in shares) \| shares	1,130
Convertible and exchangeable senior notes, outstanding principal	$ 13,605,000	$ 13,605,000
Convertible and exchangeable senior notes \| 5.00% Convertible Notes
Debt Instrument [Line Items]
Converted instrument, amount	$ 1,000

Debt Instrument, Convertible, Conversion Or Exchange Ratio

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- Definition

Debt Instrument, Convertible, Conversion Or Exchange Shares

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
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- Definition

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

+ References

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-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

+ References

No definition available.

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- Definition

Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

+ References

No definition available.

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- Definition

Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

+ References

No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- 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.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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