Financing (Senior Notes) (Narrative) (Details) $ in Billions	3 Months Ended
Mar. 31, 2017 USD ($) d Rate
Financing
Unsecured senior notes description	The Company has issued a cumulative $1.9 billion aggregate principal amount of unsecured senior notes, which are due between January 2021 and March 2026, with United Missouri Bank as trustee. Interest on the senior notes, ranging from 3.550% to 4.875%, is payable semi-annually and is computed on the basis of a 360-day year.
Debt instrument covenant description	Each of the senior notes is subject to certain customary covenants, with which the Company complied as of March 31, 2017.
Senior notes [Member]
Financing
Aggregate principle of unsecured senior notes \| $	$ 1.9
Maturity date range, minimum	Jan. 14, 2021
Maturity date range, maximum	Mar. 08, 2026
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%

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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