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Class Of Warrant Or Right, Exercise Period

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Conversion Of Notes Base Conversion Price

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Fair Value Measurement Debt Basis Amount

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Percentage Of Purchase Price Of Notes Which Should Be Paid Upon Fundamental Change

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The amount of subsequent adjustments to additional paid in capital for convertible financial instruments where a component of equity and a component of debt are recognized.

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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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Remaining amortization period for discount on the liability component of convertible debt which may be settled in cash upon conversion, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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

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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.

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

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

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Convertible Senior Notes - Narrative (Details) shares in Millions		3 Months Ended		6 Months Ended	12 Months Ended
	Nov. 01, 2018 USD ($) shares	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Jun. 30, 2018 USD ($)	Dec. 31, 2019 USD ($) day trading_day shares	Dec. 31, 2018 USD ($)	Jun. 30, 2017 USD ($)	Nov. 30, 2013 USD ($)
Debt Conversion [Line Items]
Percentage of purchase price of notes which should be paid upon fundamental change (percent)					100.00%
Benefit from exercise of 2018 Note Hedges						$ 766,857,000
Estimated fair value of the note based on the closing trading price					$ 100	100
Warrant exercise period \| trading_day					60
Stock Price Trigger Measurement
Debt Conversion [Line Items]
Number of days out of 30 that common stock price exceeded conversion price, days \| day					20
Number of consecutive trading days in a period \| day					30
Threshold percentage of stock price trigger (percent)					130.00%
Notes Price Trigger Measurement
Debt Conversion [Line Items]
Number of days out of 30 that common stock price exceeded conversion price, days \| day					5
Number of consecutive trading days in a period \| day					5
Threshold percentage of stock price trigger (percent)					98.00%
Conversion of notes base conversion price					$ 1,000
2022 Notes
Debt Conversion [Line Items]
Notes, par value					$ 782,491,000	782,500,000	$ 782,500,000
Contractual interest rate, notes							0.00%
Remaining life of the note					29 months
2018 Notes
Debt Conversion [Line Items]
Notes, par value								$ 575,000,000.0
Contractual interest rate, notes								0.00%
Settlement of principal	$ 161,800,000			$ 413,200,000
Settlement of 2018 Notes conversion feature (in shares) \| shares	1.3
Loss on extinguishment of debt						(4,100,000)
Conversion option settlement, reduction to additional paid-in capital						6,400,000
Conversion option settlement, fair value adjustments						773,300,000
2018 Note Hedge
Debt Conversion [Line Items]
Benefit from exercise of 2018 Note Hedges						$ 766,900,000
2018 Warrants
Debt Conversion [Line Items]
Number of shares to be issued upon exercise of the Warrants (in shares) \| shares					4.3
2022 Warrants
Debt Conversion [Line Items]
Number of potential securities issued upon automatic exercise of the Warrants (in shares) \| shares					1.6
Scenario, Forecast \| 2022 Notes
Debt Conversion [Line Items]
Settlement of principal		$ 5,200,000	$ 2,500,000