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

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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 (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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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Debt (Consolidated Debt) (Details) - USD ($)	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 4,948,000,000		$ 4,750,000,000
Unamortized debt issuance costs	(37,407,000)		(35,263,000)
Net unamortized premium (discount)	(10,282,000)		(8,662,000)
Long-term debt, net	$ 4,900,311,000		4,706,075,000
4.25% Notes Due 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.25%
Debt Instrument, Face Amount	$ 0		550,000,000
3.20% Notes Due 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.20%
Debt Instrument, Face Amount	$ 250,000,000		250,000,000
5.00% Notes Due 2026 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.00%
Debt Instrument, Face Amount	$ 650,000,000		650,000,000
3.25% Notes Due 2030 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.25%	3.25%
Debt Instrument, Face Amount	$ 500,000,000	$ 500,000,000.0	0
6.40% Notes Due 2037 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.40%
Debt Instrument, Face Amount	$ 250,000,000		250,000,000
4.20% Notes Due 2042 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.20%
Debt Instrument, Face Amount	$ 250,000,000		250,000,000
5.15% Notes Due 2043 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.15%
Debt Instrument, Face Amount	$ 550,000,000		550,000,000
4.20% Notes Due 2045 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.20%
Debt Instrument, Face Amount	$ 250,000,000		250,000,000
4.25% Notes Due 2046 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.25%
Debt Instrument, Face Amount	$ 500,000,000		500,000,000
4.20% Notes Due 2047 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.20%
Debt Instrument, Face Amount	$ 500,000,000		500,000,000
4.85% Notes Due 2049 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.85%
Debt Instrument, Face Amount	$ 500,000,000		500,000,000
3.95% Notes Due 2050 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.95%
Debt Instrument, Face Amount	$ 500,000,000		500,000,000
Commercial Paper [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 248,000,000		$ 0