Debt Financing Arrangements (Long-Term Debt) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2014	Jun. 30, 2007
Debt Instruments [Line Items]
Long-term Debt	$ 6,512	$ 5,582
Current maturities	(1,165)	(24)
Total long-term debt	5,347	5,558
Convertible senior notes point eight seven five percent due two thousand fourteen [Member]
Debt Instruments [Line Items]
Long-term Debt	1,144	0
Debt Instrument, Face Amount	1,150
Interest rate stated percentage	0.875%		0.875%
Debt instrument, maturity year	2014
Debentures four point four seven nine percent due in two thousand twenty one [Member]
Debt Instruments [Line Items]
Long-term Debt	746	773
Debt Instrument, Face Amount		750
Interest rate stated percentage		4.479%
Debt instrument, maturity year		2021
Debentures five point four five percent due in two thousand eighteen [Member]
Debt Instruments [Line Items]
Long-term Debt	699	701
Debt Instrument, Face Amount		700
Interest rate stated percentage		5.45%
Debt instrument, maturity year		2018
Debentures five point seven six five percent due in two thousand forty one [Member]
Debt Instruments [Line Items]
Long-term Debt	600	600
Debt Instrument, Face Amount		596
Interest rate stated percentage		5.765%
Debt instrument, maturity year		2041
Debentures five point three seven five percent due in two thousand thirty five [Member}
Debt Instruments [Line Items]
Long-term Debt	588	589
Debt Instrument, Face Amount		600
Interest rate stated percentage		5.375%
Debt instrument, maturity year		2035
Debentures five point nine three five percent due in two thousand thirty two [Member]
Debt Instruments [Line Items]
Long-term Debt	416	417
Debt Instrument, Face Amount		420
Interest rate stated percentage		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	376	378
Debt Instrument, Face Amount		570
Interest rate stated percentage		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	373	375
Debt Instrument, Face Amount		528
Interest rate stated percentage		4.535%
Debt instrument, maturity year		2042
Debentures eight point three seven five percent due in two thousand seventeen [ Member]
Debt Instruments [Line Items]
Long-term Debt	294	294
Debt Instrument, Face Amount		295
Interest rate stated percentage		8.375%
Debt instrument, maturity year		2017
Debentures seven point five percent due in two thousand twenty seven [Member]
Debt Instruments [Line Items]
Long-term Debt	186	186
Debt Instrument, Face Amount		187
Interest rate stated percentage		7.50%
Debt instrument, maturity year		2027
Debentures seven percent due in two thousand thirty one [Member]
Debt Instruments [Line Items]
Long-term Debt	184	184
Debt Instrument, Face Amount		185
Interest rate stated percentage		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	182	182
Debt Instrument, Face Amount		182
Interest rate stated percentage		6.625%
Debt instrument, maturity year		2029
Debentures six point four five percent due in two thousand thirty eight [Member]
Debt Instruments [Line Items]
Long-term Debt	153	153
Debt Instrument, Face Amount		154
Interest rate stated percentage		6.45%
Debt instrument, maturity year		2038
Debentures six point nine five due in two thousand ninety seven [Member]
Debt Instruments [Line Items]
Long-term Debt	170	170
Debt Instrument, Face Amount		172
Interest rate stated percentage		6.95%
Debt instrument, maturity year		2097
Debentures six point seven five percent due in two thousand twenty seven [Member]
Debt Instruments [Line Items]
Long-term Debt	122	122
Debt Instrument, Face Amount		124
Interest rate stated percentage		6.75%
Debt instrument, maturity year		2027
Other [Member]
Debt Instruments [Line Items]
Long-term Debt	$ 279	$ 458