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Debt Issuance Cost Amortization Period

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Issuance Of Common Stock For Repayment Of Senior Debt, Value

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Percentage of Underwriting Fee

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

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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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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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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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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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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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Amount, after accumulated amortization, of debt discount.

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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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The cash outflow for a long-term debt where the holder has highest claim on the entity's asset in case of bankruptcy or liquidation during the period.

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Exchangeable Senior Notes - Additional Information (Details)					1 Months Ended	12 Months Ended
	Nov. 02, 2020 USD ($) shares	Oct. 01, 2020 USD ($) shares	Dec. 31, 2019	Jun. 21, 2013 USD ($)	Sep. 30, 2015	Dec. 31, 2020 USD ($) day	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2016 USD ($)
Debt Instrument [Line Items]
Cash paid for repurchase of debt						$ 2,014,730,000	$ 1,977,805,000	$ 1,109,854,000
2015 Notes
Debt Instrument [Line Items]
Principal amount of notes issued									$ 575,000,000
Fixed interest rate						3.125%			3.125%
Related debt issuance costs									$ 11,992,000
Underwriting fee percentage					2.00%
Amortization period					5 years
Conversion ratio			0.01100
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%
Notes exchange, threshold percentage						130.00%
Notes exchange, threshold trading days \| day						20
Notes exchange, threshold consecutive trading days \| day						30
Effective interest rate						4.00%
2015 Notes \| Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Repurchase of exchangeable senior notes		$ 71,513,000
Repurchase of exchangeable senior notes with common stock (in shares) \| shares		124,819
Repurchase of exchangeable senior notes with common stock		$ 13,495,000
2015 Notes \| Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Repurchase of exchangeable senior notes	$ 503,432,000
Repurchase of exchangeable senior notes with common stock (in shares) \| shares	1,198,962
Repurchase of exchangeable senior notes with common stock	$ 138,900,000
2015 Notes \| Debt Instrument, Redemption, Period Three
Debt Instrument [Line Items]
Repurchase of exchangeable senior notes	$ 55,000
2015 Notes \| Minimum
Debt Instrument [Line Items]
Number of days of written notice to holders of notes required for redemption					30 days
2015 Notes \| Maximum
Debt Instrument [Line Items]
Number of days of written notice to holders of notes required for redemption					60 days
2013 Notes
Debt Instrument [Line Items]
Principal amount of notes issued				$ 250,000,000
Fixed interest rate				2.375%
Related debt issuance costs				$ 1,672,000
Debt, measurement input				1.50%
Unamortized cash discount				$ 3,750,000
Amortization period				5 years