Financing (Senior Notes) (Narrative) (Details) $ in Millions		9 Months Ended
May 20, 2019 USD ($) d Rate	Sep. 30, 2019 USD ($) d Rate
$500 million, 3.900% Senior Notes due 2029 [Member]
Financing
Senior notes, face amount \| $	$ 500	$ 500
Interest rate of senior notes	3.90%	3.90%
Percentage of face value of debt instrument	99.991%
Number of days in annual interest calculation period \| d	360
Senior notes [Member]
Financing
Aggregate principle of unsecured senior notes \| $		$ 3,700
Number of days in annual interest calculation period \| d		360
Minimum [Member] \| Senior notes [Member]
Financing
Interest rate of senior notes		3.55%
Maximum [Member] \| Senior notes [Member]
Financing
Interest rate of senior notes		4.875%

The percent of face value, at which the debt instrument was offered to the public.

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The number of days in a year used to calculate interest.

+ References

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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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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.

+ References

No definition available.

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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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