Debt Instrument, Convertible, Associated Derivative Transactions, Number Of Shares1

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- Definition

Debt Instrument, Convertible, Terms Of Conversion Feature, Conversion Amount

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No definition available.

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- Definition

Debt Instrument, Covenant Repurchase Price, Percentage

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- Definition

Debt Instrument, Redemption Covenant, Percent Of Conversion Price, Last Reported Sale Price Of Common Stock

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- Definition

Line of Credit Facility, Maximum Borrowing Capacity, Option to Increase, Amount

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Line of Credit Facility, Maturity, Conditional Restrictions, Value of Unrestricted Cash on Hand Threshold

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- Definition

Adjustment to additional paid in capital resulting from the recognition of convertible debt instruments as two separate components - a debt component and an equity component. This bifurcation may result in a basis difference associated with the liability component that represents a temporary difference for purposes of applying accounting for income taxes. The initial recognition of deferred taxes for the tax effect of that temporary difference is as an adjustment to additional paid in capital.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

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- Definition

The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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- Definition

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

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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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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.

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- Definition

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

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- Definition

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

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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.

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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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- Definition

The amount of the liability for the conversion option reclassified to stockholders' equity when the embedded option no longer required separation from the host instrument.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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- Definition

The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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- Definition

The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).

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Debt - Narrative (Details)	1 Months Ended			12 Months Ended
Debt - Narrative (Details)	Dec. 31, 2018 USD ($)	Nov. 30, 2018 USD ($) d $ / shares shares	Jun. 30, 2017 USD ($) $ / shares	Dec. 31, 2019 USD ($) d	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 19, 2018 USD ($)
Debt Instrument [Line Items]
Proceeds from issuance of convertible debt, net of issuance costs				$ 0	$ 836,600,000	$ 389,000,000.0
Equity component of convertible note issuance, net of issuance costs					(218,900,000)
Proceeds from sale of warrants				0	183,800,000	0
Senior convertible notes due 2023
Debt Instrument [Line Items]
Equity component of convertible note issuance, net of issuance costs					171,600,000
Senior convertible notes due 2022
Debt Instrument [Line Items]
Equity component of convertible note issuance, net of issuance costs						70,600,000
Senior Notes \| Senior convertible notes due 2023
Debt Instrument [Line Items]
Principal amount	$ 850,000,000.0	$ 850,000,000.0		$ 850,000,000.0	850,000,000.0
Interest rate on convertible notes (as a percent)		0.75%	0.75%
Proceeds from issuance of convertible debt, net of issuance costs		$ 836,600,000
Conversion ratio		0.0060869	0.0100918
Conversion amount		$ 1,000
Conversion price of convertible notes (USD per share) \| $ / shares		$ 164.29
Holder's repurchase price percentage in event of fundamental change (as a percent)				100.00%
Number of trading days \| d		60
Proportion of conversion price (as a percent)				130.00%
Redemption price (as a percent)				100.00%
Stock counterparties to acquire with warrants purchased (shares) \| shares		5,200,000
Proceeds from sale of warrants		$ 183,800,000
Exercise price of warrants or rights (USD per share) \| $ / shares		$ 198.38
Senior Notes \| Senior convertible notes due 2022
Debt Instrument [Line Items]
Principal amount	$ 400,000,000.0		$ 400,000,000.0	$ 400,000,000.0	$ 400,000,000.0
Interest rate on convertible notes (as a percent)			0.75%
Proceeds from issuance of convertible debt, net of issuance costs			$ 389,000,000.0
Conversion amount			$ 1,000
Conversion price of convertible notes (USD per share) \| $ / shares			$ 99.09
Holder's repurchase price percentage in event of fundamental change (as a percent)				100.00%
Proportion of conversion price (as a percent)				140.00%
Redemption price (as a percent)				100.00%
Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity of revolving credit agreement				$ 200,000,000.0			$ 200,000,000.0
Option to increase revolving line of credit							$ 500,000,000.0
Value of unrestricted cash on hand threshold				$ 100,000,000.0
Line of Credit \| Minimum
Debt Instrument [Line Items]
Interest rate on convertible notes (as a percent)	0.375%				0.375%
Unused capacity fee (as a percent)	0.20%
Line of Credit \| Maximum
Debt Instrument [Line Items]
Interest rate on convertible notes (as a percent)	1.00%				1.00%
Unused capacity fee (as a percent)	0.30%
Additional Paid-In Capital
Debt Instrument [Line Items]
Equity component of convertible note issuance, net of issuance costs					$ (218,900,000)
Additional Paid-In Capital \| Senior convertible notes due 2023
Debt Instrument [Line Items]
Equity component of convertible note issuance, net of issuance costs					171,600,000
Additional Paid-In Capital \| Senior convertible notes due 2022
Debt Instrument [Line Items]
Equity component of convertible note issuance, net of issuance costs						70,600,000
Additional Paid-In Capital \| Senior Notes \| Senior convertible notes due 2023
Debt Instrument [Line Items]
Recognized additional paid-in capital from cash conversion option					$ 174,400,000
Additional Paid-In Capital \| Senior Notes \| Senior convertible notes due 2022
Debt Instrument [Line Items]
Recognized additional paid-in capital from cash conversion option						$ 72,600,000
Debt Instrument Conversion Term One \| Senior Notes \| Senior convertible notes due 2023 \| Minimum
Debt Instrument [Line Items]
Number of trading days \| d				20
Proportion of applicable conversion price (as a percent)				130.00%
Debt Instrument Conversion Term One \| Senior Notes \| Senior convertible notes due 2023 \| Maximum
Debt Instrument [Line Items]
Number of trading days \| d				30
Debt Instrument Conversion Term One \| Senior Notes \| Senior convertible notes due 2022 \| Minimum
Debt Instrument [Line Items]
Number of trading days \| d				20
Proportion of applicable conversion price (as a percent)				130.00%
Debt Instrument Conversion Term One \| Senior Notes \| Senior convertible notes due 2022 \| Maximum
Debt Instrument [Line Items]
Number of trading days \| d				30
Debt Instrument Conversion Term Two \| Senior Notes \| Senior convertible notes due 2023
Debt Instrument [Line Items]
Number of trading days \| d				5
Debt Instrument Conversion Term Two \| Senior Notes \| Senior convertible notes due 2023 \| Maximum
Debt Instrument [Line Items]
Number of trading days \| d				5
Proportion of applicable conversion price (as a percent)				98.00%
Debt Instrument Conversion Term Two \| Senior Notes \| Senior convertible notes due 2022
Debt Instrument [Line Items]
Number of trading days \| d				5
Debt Instrument Conversion Term Two \| Senior Notes \| Senior convertible notes due 2022 \| Maximum
Debt Instrument [Line Items]
Number of trading days \| d				5
Proportion of applicable conversion price (as a percent)				98.00%
Designated as Hedging Instrument \| Senior Notes \| Senior convertible notes due 2023
Debt Instrument [Line Items]
Stock issued upon conversion of senior notes (shares) \| shares		5,200,000
Equity component of convertible note issuance, net of issuance costs		$ 218,900,000
London Interbank Offered Rate (LIBOR) \| Line of Credit \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	1.375%
London Interbank Offered Rate (LIBOR) \| Line of Credit \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	2.00%