Represents the percentage of debt discount that was originally recognized at the issuance of the instrument.

No definition available.

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- Definition

The principal amount of notes used as denominator for purposes of computing the conversion ratio of convertible debt.

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No definition available.

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- Definition

Debt Issuance Cost Amortization Period

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No definition available.

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- Definition

Percentage of Underwriting Fee

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No definition available.

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- Definition

Represents the percentage of principal amount used in computation of the redemption price to be paid on conversion of convertible notes at the request of the debt holders and upon the occurrence of a designated event.

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No definition available.

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- Definition

Represents the number of days of written notice to be made to the holders of the notes required for redemption.

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No definition available.

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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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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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- Definition

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

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No definition available.

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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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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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

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

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No definition available.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Amount, after accumulated amortization, of debt discount.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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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Exchangeable Senior Notes - Additional Information (Detail)		1 Months Ended	9 Months Ended
	Jun. 21, 2013 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2018 USD ($) d	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Debt Instrument [Line Items]
Related debt issuance costs			$ 4,808,000		$ 6,620,000
Total consideration paid for repurchase			$ 787,939,000	$ 1,020,144,000
Exchangeable Senior Notes 3.125% due 2035 (the 2015 Notes)
Debt Instrument [Line Items]
Principal amount of notes issued		$ 575,000,000
Debt stated interest rate		3.125%	3.125%
Related debt issuance costs		$ 11,992,000
Underwriting fee percentage		2.00%
Amortization period		5 years
Conversion ratio			10.75
Debt amount denomination for conversion into common stock			$ 1,000
Redemption price as percentage of principal amount of notes plus accrued and unpaid interest		100.00%
Redemption price as percentage of principal amount of notes at request of debt holders and upon occurrence of designated event		100.00%
Effective interest rate on the liability component			4.00%
Exchangeable Senior Notes 3.125% due 2035 (the 2015 Notes) \| Minimum
Debt Instrument [Line Items]
Number of days of written notice to holders of notes required for redemption		30 days
Exchangeable Senior Notes 3.125% due 2035 (the 2015 Notes) \| Maximum
Debt Instrument [Line Items]
Number of days of written notice to holders of notes required for redemption		60 days
Exchangeable Senior Notes 2.375% due 2033 (the 2013 Notes)
Debt Instrument [Line Items]
Principal amount of notes issued	$ 250,000,000
Debt stated interest rate	2.375%
Related debt issuance costs	$ 1,672,000		$ 10,000	35,000
Redemption price as percentage of principal amount of notes plus accrued and unpaid interest	100.00%
Notes exchange, threshold percentage			130.00%
Notes exchange, threshold trading days \| d			20
Notes exchange, threshold consecutive trading days \| d			30
Discount rate	1.50%
Unamortized cash discount	$ 3,750,000		$ 230,000	183,000
Amortization period	5 years
Effective interest rate on the liability component			4.00%
Principal amount repurchased			$ 49,259,000	13,786,000
Total consideration paid for repurchase			$ 80,270,000	$ 19,853,000
Exchangeable Senior Notes 2.375% due 2033 (the 2013 Notes) \| Minimum
Debt Instrument [Line Items]
Number of days of written notice to holders of notes required for redemption	30 days
Exchangeable Senior Notes 2.375% due 2033 (the 2013 Notes) \| Maximum
Debt Instrument [Line Items]
Number of days of written notice to holders of notes required for redemption	60 days