Debt Financing Arrangements (Long-Term Debt) (Details) € in Millions, $ in Millions						12 Months Ended
	Dec. 03, 2018 EUR (€)	Sep. 12, 2018 EUR (€)	Sep. 29, 2017	Sep. 14, 2017 USD ($)	Apr. 15, 2017 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2018 EUR (€)
Debt Instruments [Line Items]
Long-term Debt						$ 8,280	$ 6,636
Current maturities						(582)	(13)
Total long-term debt						7,698	6,623
Notes One Point Seventy Five Percent Due In Two Thousand Twenty-Three [Member]
Debt Instruments [Line Items]
Long-term Debt						$ 682	714
Debt Instrument, Face Amount | €								€ 600
Debt Instrument, Interest Rate, Stated Percentage						1.75%		1.75%
Debt instrument, maturity year						2023
Notes Four Point Five Percent due Two Thousand Forty-Nine [Member]
Debt Instruments [Line Items]
Long-term Debt						$ 587	0
Debt Instrument, Face Amount | €	€ 600
Debt Instrument, Interest Rate, Stated Percentage	4.50%
Debt Instrument, Maturity Date	Mar. 15, 2049
Notes Two Point Five Percent Due in Two Thousand Twenty-Six [Member]
Debt Instruments [Line Items]
Long-term Debt						993	992
Debt Instrument, Face Amount						$ 1,000
Debt Instrument, Interest Rate, Stated Percentage						2.50%		2.50%
Debt instrument, maturity year						2026
Notes One Percent Due in Two Thousand Twenty-Five [Member]
Debt Instruments [Line Items]
Long-term Debt						$ 736	0
Debt Instrument, Face Amount		€ 650				$ 744		€ 650
Debt Instrument, Interest Rate, Stated Percentage		1.00%				1.00%		1.00%
Debt Instrument, Maturity Date		Sep. 12, 2025				Sep. 12, 2025
Floating Rate Notes Due In Two Thousand Nineteen [Member]
Debt Instruments [Line Items]
Long-term Debt						$ 572	599
Debt Instrument, Face Amount | €								€ 500
Debt instrument, maturity year						2019
Debentures four point four seven nine percent due in two thousand twenty one [Member]
Debt Instruments [Line Items]
Long-term Debt						$ 493	501
Debt Instrument, Face Amount						$ 516
Debt Instrument, Interest Rate, Stated Percentage						4.479%		4.479%
Debt instrument, maturity year						2021
Notes Three Point Seventy-Five Percent Due in Two Thousand Forty-Seven [Member]
Debt Instruments [Line Items]
Long-term Debt						$ 493	492
Debt Instrument, Face Amount				$ 500		$ 500
Debt Instrument, Interest Rate, Stated Percentage				3.75%		3.75%		3.75%
Debt Instrument, Maturity Date				Sep. 15, 2047		Sep. 15, 2047
Debentures five point three seven five percent due in two thousand thirty five [Member}
Debt Instruments [Line Items]
Long-term Debt						$ 461	460
Debt Instrument, Face Amount						$ 470
Debt Instrument, Interest Rate, Stated Percentage						5.375%		5.375%
Debt instrument, maturity year						2035
Notes Three Point Three Hundred Seventy-Five Percent due in Two Thousand Twenty-Two [Member]
Debt Instruments [Line Items]
Long-term Debt						$ 398	0
Debt Instrument, Face Amount | €	€ 400
Debt Instrument, Interest Rate, Stated Percentage	3.375%
Debt Instrument, Maturity Date	Mar. 15, 2022
Debentures five point seven six five percent due in two thousand forty one [Member]
Debt Instruments [Line Items]
Long-term Debt						378	378
Debt Instrument, Face Amount						$ 378
Debt Instrument, Interest Rate, Stated Percentage						5.765%		5.765%
Debt instrument, maturity year						2041
Debentures five point nine three five percent due in two thousand thirty two [Member]
Debt Instruments [Line Items]
Long-term Debt						$ 378	378
Debt Instrument, Face Amount						$ 383
Debt Instrument, Interest Rate, Stated Percentage						5.935%		5.935%
Debt instrument, maturity year						2032
Debentures four point zero one six percent due in two thousand forty three [Member]
Debt Instruments [Line Items]
Long-term Debt						$ 386	383
Debt Instrument, Face Amount						$ 570
Debt Instrument, Interest Rate, Stated Percentage						4.016%		4.016%
Debt instrument, maturity year						2043
Debentures four point five three five percent due in two thousand forty two [Member]
Debt Instruments [Line Items]
Long-term Debt						$ 382	379
Debt Instrument, Face Amount						$ 528
Debt Instrument, Interest Rate, Stated Percentage						4.535%		4.535%
Debt instrument, maturity year						2042
Debentures eight point three seven five percent due in two thousand seventeen [ Member]
Debt Instruments [Line Items]
Debt Instrument, Face Amount					$ 261		$ 261
Debt Instrument, Interest Rate, Stated Percentage					8.375%		8.375%
Debt Instrument, Maturity Date					Apr. 15, 2017		Apr. 15, 2017
Debentures seven percent due in two thousand thirty one [Member]
Debt Instruments [Line Items]
Long-term Debt						$ 163	$ 163
Debt Instrument, Face Amount						$ 164
Debt Instrument, Interest Rate, Stated Percentage						7.00%		7.00%
Debt instrument, maturity year						2031
Debentures six point six two five percent due in two thousand twenty nine [Member]
Debt Instruments [Line Items]
Long-term Debt						$ 159	159
Debt Instrument, Face Amount						$ 160
Debt Instrument, Interest Rate, Stated Percentage						6.625%		6.625%
Debt instrument, maturity year						2029
Debentures six point ninety-five due in two thousand ninety seven [Member]
Debt Instruments [Line Items]
Long-term Debt						$ 155	155
Debt Instrument, Face Amount						$ 159
Debt Instrument, Interest Rate, Stated Percentage						6.95%		6.95%
Debt instrument, maturity year						2097
Debentures seven point five percent due in two thousand twenty seven [Member]
Debt Instruments [Line Items]
Long-term Debt						$ 149	150
Debt Instrument, Face Amount						$ 150
Debt Instrument, Interest Rate, Stated Percentage						7.50%		7.50%
Debt instrument, maturity year						2027
Debentures six point forty-five percent due in two thousand thirty eight [Member]
Debt Instruments [Line Items]
Long-term Debt						$ 126	126
Debt Instrument, Face Amount						$ 127
Debt Instrument, Interest Rate, Stated Percentage						6.45%		6.45%
Debt instrument, maturity year						2038
Debentures six point seventy-five percent due in two thousand twenty seven [Member]
Debt Instruments [Line Items]
Long-term Debt						$ 117	117
Debt Instrument, Face Amount						$ 118
Debt Instrument, Interest Rate, Stated Percentage						6.75%		6.75%
Debt instrument, maturity year						2027
Notes Five Point Forty-Five Percent Due In Two Thousand Eighteen [Member]
Debt Instruments [Line Items]
Debt Instrument, Face Amount							$ 559
Debt Instrument, Interest Rate, Stated Percentage			5.45%				5.45%
Debt Instrument, Maturity Date			Mar. 15, 2018				Mar. 15, 2018
Other [Member]
Debt Instruments [Line Items]
Long-term Debt						$ 472	$ 490