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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Amount, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt discount (premium).

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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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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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The effective rate on par for debt issued during the period.

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Debt - Summary of Senior Unsecured Notes (Details)	Jun. 30, 2019 USD ($)	Jun. 30, 2019 EUR (€)	Jun. 14, 2019 USD ($)	Dec. 31, 2018 USD ($)
Senior Unsecured Notes
Senior unsecured notes, net	$ 3,861,931,000			$ 3,554,470,000
Deferred financing costs	21,653,000
Unamortized discount, net	38,655,000
Unsecured senior notes
Senior Unsecured Notes
Principal Amount	3,900,000,000
Senior unsecured notes, net	3,901,000,000.0			3,590,000,000.0
Deferred financing costs	21,000,000.0			19,700,000
Unamortized discount, net	$ 18,100,000			15,800,000
Unsecured senior notes \| 2.0% Senior Notes due 2023
Senior Unsecured Notes
Principal Amount \| €		€ 500,000,000.0
Price of Par Value (percentage)	99.22%	99.22%
Original Issue Discount	$ 4,600,000
Effective Interest Rate (percentage)	2.107%	2.107%
Coupon rate (percentage)	2.00%	2.00%
Senior unsecured notes, net	$ 569,000,000.0			572,500,000
Unsecured senior notes \| 4.6% Senior Notes due 2024
Senior Unsecured Notes
Principal Amount	$ 500,000,000.0
Price of Par Value (percentage)	99.639%	99.639%
Original Issue Discount	$ 1,800,000
Effective Interest Rate (percentage)	4.645%	4.645%
Coupon rate (percentage)	4.60%	4.60%
Senior unsecured notes, net	$ 500,000,000.0			500,000,000.0
Unsecured senior notes \| 2.25% Senior Notes due 2024
Senior Unsecured Notes
Principal Amount \| €		€ 500,000,000.0
Price of Par Value (percentage)	99.448%	99.448%
Original Issue Discount	$ 2,900,000
Effective Interest Rate (percentage)	2.332%	2.332%
Coupon rate (percentage)	2.25%	2.25%
Senior unsecured notes, net	$ 569,000,000.0			572,500,000
Unsecured senior notes \| 4.0% Senior Notes due 2025
Senior Unsecured Notes
Principal Amount	$ 450,000,000.0
Price of Par Value (percentage)	99.372%	99.372%
Original Issue Discount	$ 2,800,000
Effective Interest Rate (percentage)	4.077%	4.077%
Coupon rate (percentage)	4.00%	4.00%
Senior unsecured notes, net	$ 450,000,000.0			450,000,000.0
Unsecured senior notes \| 2.250% Senior Notes due 2026
Senior Unsecured Notes
Principal Amount \| €		€ 500,000,000.0
Price of Par Value (percentage)	99.252%	99.252%
Original Issue Discount	$ 4,300,000
Effective Interest Rate (percentage)	2.361%	2.361%
Coupon rate (percentage)	2.25%	2.25%
Senior unsecured notes, net	$ 569,000,000.0			572,500,000
Unsecured senior notes \| 4.25% Senior Notes due 2026
Senior Unsecured Notes
Principal Amount	$ 350,000,000.0
Price of Par Value (percentage)	99.682%	99.682%
Original Issue Discount	$ 1,100,000
Effective Interest Rate (percentage)	4.29%	4.29%
Coupon rate (percentage)	4.25%	4.25%
Senior unsecured notes, net	$ 350,000,000.0			350,000,000.0
Unsecured senior notes \| 2.125% Senior Notes due 2027
Senior Unsecured Notes
Principal Amount \| €		€ 500,000,000.0
Price of Par Value (percentage)	99.324%	99.324%
Original Issue Discount	$ 4,200,000
Effective Interest Rate (percentage)	2.208%	2.208%
Coupon rate (percentage)	2.125%	2.125%
Senior unsecured notes, net	$ 569,000,000.0			572,500,000
Unsecured senior notes \| 3.850% Senior Notes due 2029
Senior Unsecured Notes
Principal Amount	$ 325,000,000.0		$ 325,000,000.0
Price of Par Value (percentage)	98.876%	98.876%	98.876%
Original Issue Discount	$ 3,700,000
Effective Interest Rate (percentage)	3.986%	3.986%
Coupon rate (percentage)	3.85%	3.85%	3.85%
Senior unsecured notes, net	$ 325,000,000.0			$ 0
Deferred financing costs	$ 2,900,000