Debt (Consolidated Debt) (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 4,750,000,000	$ 4,750,000,000
Unamortized debt issuance costs	(34,743,000)	(35,263,000)
Net unamortized premium (discount)	(8,871,000)	(8,662,000)
Long-term Debt	4,706,386,000	4,706,075,000
Current portion of long-term debt, net	550,949,000	0
Long-term debt, net	4,155,437,000	4,706,075,000
4.25% Notes Due 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 550,000,000	550,000,000
Debt Instrument, Interest Rate, Stated Percentage	4.25%
3.20% Notes Due 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 250,000,000	250,000,000
Debt Instrument, Interest Rate, Stated Percentage	3.20%
5.00% Notes Due 2026 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 650,000,000	650,000,000
Debt Instrument, Interest Rate, Stated Percentage	5.00%
6.40% Notes Due 2037 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 250,000,000	250,000,000
Debt Instrument, Interest Rate, Stated Percentage	6.40%
4.20% Notes Due 2042 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 250,000,000	250,000,000
Debt Instrument, Interest Rate, Stated Percentage	4.20%
5.15% Notes Due 2043 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 550,000,000	550,000,000
Debt Instrument, Interest Rate, Stated Percentage	5.15%
4.20% Notes Due 2045 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 250,000,000	250,000,000
Debt Instrument, Interest Rate, Stated Percentage	4.20%
4.25% Notes Due 2046 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 500,000,000	500,000,000
Debt Instrument, Interest Rate, Stated Percentage	4.25%
4.20% Notes Due 2047 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 500,000,000	500,000,000
Debt Instrument, Interest Rate, Stated Percentage	4.20%
4.85% Notes Due 2049 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 500,000,000	500,000,000
Debt Instrument, Interest Rate, Stated Percentage	4.85%
3.95% Notes Due 2050 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 500,000,000	$ 500,000,000
Debt Instrument, Interest Rate, Stated Percentage	3.95%

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

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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. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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