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

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- Definition

Debt Instrument, Covenant Repurchase Price, Percentage

+ References

No definition available.

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- Definition

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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- Definition

Amount of amortization expense attributable to debt issuance costs.

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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.

+ References

No definition available.

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- Definition

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

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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- Definition

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

+ References

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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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- 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

Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings, excluding amortization of debt discount (premium) and financing costs.

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- Definition

Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

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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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Debt 0.75% Senior convertible notes due 2022 Narrative (Details)	1 Months Ended	3 Months Ended		9 Months Ended
	May 31, 2017 USD ($) $ / shares	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) d	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)	Jun. 30, 2017 USD ($)	May 12, 2017
Debt Instrument [Line Items]
Aggregate principal amount		$ 400,000,000.0		$ 400,000,000.0		$ 400,000,000
Proceeds from convertible debt				0	$ 389,000,000
Non-cash interest expense				11,300,000	5,700,000
Estimated litigation liability		0		0
Senior Notes \| 0.75% Senior Convertible Notes \| Convertible Notes due 2022
Debt Instrument [Line Items]
Aggregate principal amount	$ 350,000,000.0						$ 50,000,000.0
Interest rate on convertible notes	0.75%							0.75%
Proceeds from convertible debt	$ 389,000,000
Initial conversion price of convertible notes (in dollars per share) \| $ / shares	$ 99.09
Contractual coupon interest rate		800,000	$ 800,000	2,300,000	1,100,000
Non-cash interest expense		3,400,000	3,100,000	10,000,000	4,900,000
Amortization of debt issuance costs		$ 400,000	$ 400,000	$ 1,200,000	600,000
Effective interest rate		5.10%		5.10%
Conversion price in event of fundamental change		100.00%		100.00%
Conversion multiple		$ 1,000		$ 1,000
Debt instrument, redemption price, percentage				100.00%
Debt instrument, convertible, conversion ratio	0.0100918
Senior Notes \| Additional Paid-in Capital \| 0.75% Senior Convertible Notes \| Convertible Notes due 2022
Debt Instrument [Line Items]
Amount reclassified to stockholders' equity					$ 72,600,000
Senior Notes \| Term of at least 20 trading days during a period of 30 consecutive trading days \| Minimum \| 0.75% Senior Convertible Notes \| Convertible Notes due 2022
Debt Instrument [Line Items]
Threshold consecutive trading days \| d				20
Threshold percentage of stock price trigger				130.00%
Senior Notes \| Term of at least 20 trading days during a period of 30 consecutive trading days \| Maximum \| 0.75% Senior Convertible Notes \| Convertible Notes due 2022
Debt Instrument [Line Items]
Threshold consecutive trading days \| d				30
Senior Notes \| Term of five business day period after any five consecutive trading day period \| 0.75% Senior Convertible Notes \| Convertible Notes due 2022
Debt Instrument [Line Items]
Threshold consecutive trading days \| d				5
Senior Notes \| Term of five business day period after any five consecutive trading day period \| Maximum \| 0.75% Senior Convertible Notes \| Convertible Notes due 2022
Debt Instrument [Line Items]
Threshold consecutive trading days \| d				5
Threshold percentage of stock price trigger				98.00%