Capped call options cap price.

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Cost of purchased capped call options.

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Debt instrument, convertible shares, per thousand of principal amount of notes.

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Debt issuance costs attributable to equity component.

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Description of convertible notes at option of holders.

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Notes measurement period.

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- Definition

Partially terminated capped call options.

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Principal amount per note used in conversion rate.

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No definition available.

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Amount of increase (decrease) in additional paid in capital (APIC) resulting from recognition of deferred taxes for convertible debt with a beneficial conversion feature.

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

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- Definition

Price of the entity's common stock which would be required to be attained for the conversion feature embedded in the debt instrument to become effective.

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No definition available.

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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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No definition available.

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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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- Definition

Date the debt agreement requires the first payment to be made, in CCYY-MM-DD format.

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- Definition

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

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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

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Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

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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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No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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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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Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

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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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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Price of a single share of a number of saleable stocks of a company.

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No definition available.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Convertible Senior Notes - Additional Information (Details)	1 Months Ended		6 Months Ended		12 Months Ended
	Dec. 31, 2019 USD ($) $ / shares shares	Nov. 30, 2017 USD ($) $ / shares shares	Jun. 30, 2020 USD ($) d $ / shares	Jun. 30, 2018 d	Dec. 31, 2019 USD ($) $ / shares
0.125% Convertible Senior Notes Due 2024
Debt Instrument [Line Items]
Aggregate principal amount	$ 450,000,000		$ 450,000,000		$ 450,000,000
Debt instrument, interest rate	0.125%		0.125%		0.125%
Debt instrument, maturity date	Dec. 15, 2024		Dec. 15, 2024
Debt instrument, interest rate terms			Interest is payable semiannually in arrears on June 15 and December 15 of each year, commencing on June 15, 2020.
Interest payment commencing date	Jun. 15, 2020
Debt Conversion, initial conversion rate \| shares	8.8999
Principal amount per note used in conversion rate	$ 1,000				$ 1,000
Conversion price per share \| $ / shares	$ 112.36				$ 112.36
Shares issuable upon conversion of debt \| shares	4,000,000.0
Number of trading days \| d			20
Number of consecutive trading days \| d			30
Percentage of last reported sale price to conversion price on each applicable trading day			130.00%
Description of convertible notes at option of holders			On or after June 15, 2024 until the close of business on the second scheduled trading day immediately preceding the maturity date, holders may convert all or any portion of their 2024 Notes at the conversion rate at any time regardless of whether the conditions set forth below have been met.
Redemption price, percentage			100.00%
Implied interest rate			5.16%
Debt instrument, fair value			$ 360,400,000
Difference between aggregate principal amount and estimated fair value of liability component recorded in additional paid-in capital			89,600,000
Transaction costs attributable to liability component			10,200,000
Transaction costs attributable to equity component			$ 2,600,000
Initial strike price of capped call options \| $ / shares			$ 112.36
Capped call options, cap price \| $ / shares			$ 166.46
Cost of purchased capped call options	$ 44,900,000		$ 44,900,000
Share Price \| $ / shares			$ 138.36
0.125% Convertible Senior Notes Due 2024 \| Scenario One
Debt Instrument [Line Items]
Number of trading days \| d			20
Number of consecutive trading days \| d			30
Percentage of last reported sale price to conversion price on each applicable trading day			130.00%
0.125% Convertible Senior Notes Due 2024 \| Scenario Two
Debt Instrument [Line Items]
Number of consecutive trading days \| d			10
Percentage of last reported sale price to conversion price on each applicable trading day			98.00%
Notes measurement period			5 days
1.50% Convertible Senior Notes Due 2022
Debt Instrument [Line Items]
Aggregate principal amount	$ 92,000,000	$ 115,000,000.0	$ 92,000,000		$ 92,000,000
Debt instrument, interest rate		1.50%	1.50%
Debt instrument, maturity date		Nov. 01, 2022	Nov. 01, 2022
Debt instrument, interest rate terms			Interest is payable semiannually in arrears on May 1 and November 1 of each year, commencing on May 1, 2018
Interest payment commencing date		May 01, 2018
Debt Conversion, initial conversion rate \| shares		29.6626
Principal amount per note used in conversion rate		$ 1,000
Conversion price per share \| $ / shares		$ 33.71
Shares issuable upon conversion of debt \| shares		3,400,000
Number of trading days \| d			20	30
Number of consecutive trading days \| d			30
Percentage of last reported sale price to conversion price on each applicable trading day			130.00%
Description of convertible notes at option of holders			On or after May 1, 2022, until the close of business on the second scheduled trading day immediately preceding the maturity date, holders may convert all or any portion of their 2022 Notes at the conversion rate at any time regardless of whether the conditions set forth below have been met.
Redemption price, percentage			100.00%
Implied interest rate			6.93%
Debt instrument, fair value			$ 92,100,000
Difference between aggregate principal amount and estimated fair value of liability component recorded in additional paid-in capital			$ 22,900,000
Transaction costs attributable to liability component		$ 2,500,000
Transaction costs attributable to equity component		800,000
Initial strike price of capped call options \| $ / shares			$ 33.71
Capped call options, cap price \| $ / shares			47.20
Cost of purchased capped call options		12,900,000
Share Price \| $ / shares			$ 138.36
1.50% Convertible Senior Notes Due 2022 \| Scenario One
Debt Instrument [Line Items]
Number of trading days \| d			20
Number of consecutive trading days \| d			30
Percentage of last reported sale price to conversion price on each applicable trading day			130.00%
1.50% Convertible Senior Notes Due 2022 \| Scenario Two
Debt Instrument [Line Items]
Number of consecutive trading days \| d			5
Percentage of last reported sale price to conversion price on each applicable trading day			98.00%
Notes measurement period			5 days
1.50% Convertible Senior Notes Due 2022 Repurchase
Debt Instrument [Line Items]
Implied interest rate	4.64%				4.64%
Repayments of debt					$ 57,800,000
Repurchase of aggregate principal amount	$ 23,000,000.0				23,000,000.0
Loss on extinguishment of convertible notes					1,400,000
Remaining consideration allocated to reacquisition of equity component					36,700,000
Partially terminated capped call options					5,800,000
Option to Purchase \| 0.125% Convertible Senior Notes Due 2024
Debt Instrument [Line Items]
Aggregate principal amount	$ 75,000,000.0				$ 75,000,000.0
Option to Purchase \| 1.50% Convertible Senior Notes Due 2022
Debt Instrument [Line Items]
Aggregate principal amount		$ 15,000,000.0