Financing (Senior Notes) (Narrative) (Details) $ in Millions		9 Months Ended
Mar. 08, 2016 USD ($) d Rate	Sep. 30, 2016 USD ($) 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 UMB 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.
Aggregate principle of unsecured senior notes \| $		$ 1,900
Maturity date range, minimum		Jan. 14, 2021
Maturity date range, maximum		Mar. 08, 2026
Number of days in annual interest calculation period \| d		360
Debt instrument covenant description		Each of the senior notes is subject to certain customary covenants, with which the Company complied as of September 30, 2016.
Minimum [Member]
Financing
Interest rate of senior notes		3.55%
Maximum [Member]
Financing
Interest rate of senior notes		4.875%
$500 million, 3.550% Senior Notes due 2026 [Member]
Financing
Issuance date of senior notes	Mar. 08, 2016
Face amount of senior notes \| $	$ 500
Percentage of face value of debt instrument	99.832%
Interest rate of senior notes	3.55%
Number of days in annual interest calculation period \| d	360

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

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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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