Long-Term Debt (Scheduled Remaining Maturity Of Long-Term Debt) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
2014	$ 6,998
2015	18,860
2016	12,984
2017	12,199
2018	4,581
2019 and thereafter	11,791
Derivative, Amount of Hedged Item	500	445
Long-term debt	67,913	69,465
Unsecured Debt [Member]
Debt Instrument [Line Items]
2014	1,670
2015	4,969
2016	1,868
2017	3,981
2018	1,186
2019 and thereafter	9,007
Derivative, Amount of Hedged Item	500	445
Long-term debt	23,181	27,191
Unsecured Debt [Member] | Long-term Debt [Member]
Debt Instrument [Line Items]
2014	1,760
2015	5,026
2016	1,934
2017	4,059
2018	1,278
2019 and thereafter	10,115
Derivative, Amount of Hedged Item	500
Long-term debt	24,672
Unsecured Debt [Member] | Original Issue Discount [Member]
Debt Instrument [Line Items]
2014	(90)
2015	(57)
2016	(66)
2017	(78)
2018	(92)
2019 and thereafter	(1,108)
Derivative, Amount of Hedged Item	0
Long-term debt	(1,491)
Secured Debt [Member]
Debt Instrument [Line Items]
Derivative, Amount of Hedged Item	0	0
Long-term debt	44,732	42,274
Secured Debt [Member] | Long-term Debt [Member]
Debt Instrument [Line Items]
2014	5,328
2015	13,891
2016	11,116
2017	8,218
2018	3,395
2019 and thereafter	2,784
Derivative, Amount of Hedged Item	0
Long-term debt	$ 44,732