Financing Receivables and Allowance For Losses On Financing Receivables (Allowance for Losses on Financing Receivables ) (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total balance	$ 5,288	$ 5,205	$ 4,985	$ 6,190
Provision charged	2,517	1,606
Other	(89)	(100)
Gross write-offs	(2,909)	(3,273)
Recoveries	784	782
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total balance	902	1,290	1,041	1,530
Provision charged	366	269
Other	(7)	(69)
Gross write-offs	(604)	(537)
Recoveries	106	97
Commercial Portfolio Segment [Member] | Americas CLL Financing Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total balance	480	662	490	889
Provision charged	182	57
Other	(1)	(30)
Gross write-offs	(249)	(306)
Recoveries	58	52
Commercial Portfolio Segment [Member] | Europe CLL Financing Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total balance	329	484	445	400
Provision charged	146	158
Other	1	(15)
Gross write-offs	(304)	(95)
Recoveries	41	36
Commercial Portfolio Segment [Member] | Asia CLL Financing Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total balance	72	87	80	157
Provision charged	39	13
Other	(7)	(3)
Gross write-offs	(47)	(89)
Recoveries	7	9
Commercial Portfolio Segment [Member] | Other CLL Financing Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total balance	0	1	6	4
Provision charged	(3)	0
Other	0	(1)
Gross write-offs	(3)	(2)
Recoveries	0	0
Commercial Portfolio Segment [Member] | CLL Financing Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total balance	881	1,234	1,021	1,450
Provision charged	364	228
Other	(7)	(49)
Gross write-offs	(603)	(492)
Recoveries	106	97
Commercial Portfolio Segment [Member] | Energy Financial Services Financing Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total balance	8	12	9	26
Provision charged	(1)	10
Other	0	0
Gross write-offs	0	(24)
Recoveries	0	0
Commercial Portfolio Segment [Member] | GECAS Financing Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total balance	11	32	8	17
Provision charged	3	26
Other	0	0
Gross write-offs	0	(11)
Recoveries	0	0
Commercial Portfolio Segment [Member] | Other Financing Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total balance	2	12	3	37
Provision charged	0	5
Other	0	(20)
Gross write-offs	(1)	(10)
Recoveries	0	0
Commercial Real Estate Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total balance	235	787	320	1,089
Provision charged	(19)	45
Other	(3)	(15)
Gross write-offs	(65)	(339)
Recoveries	2	7
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total balance	4,151	3,128	3,624	3,571
Provision charged	2,170	1,292
Other	(79)	(16)
Gross write-offs	(2,240)	(2,397)
Recoveries	676	678
Consumer Portfolio Segment [Member] | Non US residential mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total balance	517	481	480	546
Provision charged	125	65
Other	(1)	(2)
Gross write-offs	(113)	(165)
Recoveries	26	37
Consumer Portfolio Segment [Member] | Non US installment and revolving credit [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total balance	663	665	623	717
Provision charged	279	220
Other	(32)	(8)
Gross write-offs	(498)	(543)
Recoveries	291	279
Consumer Portfolio Segment [Member] | US installment and revolving credit [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total balance	2,714	1,724	2,282	2,008
Provision charged	1,660	937
Other	(50)	(5)
Gross write-offs	(1,464)	(1,488)
Recoveries	286	272
Consumer Portfolio Segment [Member] | Non US auto [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total balance	62	79	67	101
Provision charged	24	15
Other	(5)	(9)
Gross write-offs	(62)	(77)
Recoveries	38	49
Consumer Portfolio Segment [Member] | Consumer Other Financing Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total balance	195	179	172	199
Provision charged	82	55
Other	9	8
Gross write-offs	(103)	(124)
Recoveries	$ 35	$ 41