Net Property and Lease Commitments (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Property, Plant and Equipment [Line Items]
Property Plant And Equipment Capitalization Policy Useful Life Term, Minimum	1 year
Capitalization useful life policy	more than one year
Property, Plant and Equipment, Net, by Type [Abstract]
Net property	$ 24,942	$ 22,371
Depreciation, Depletion and Amortization [Abstract]
Total	6,179	5,376	5,900
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance	266	331
Liabilities settled	(8)	(6)
Revision to estimates	9	(59)
Ending balance	267	266	331
Operating Leases, Future Minimum Payments Due [Abstract]
Operating Leases, Future Minimum Payments Due - 2013	269
Operating Leases, Future Minimum Payments, Due - 2014	230
Operating Leases, Future Minimum Payments, Due - 2015	178
Operating Leases, Future Minimum Payments, Due - 2016	129
Operating Leases, Future Minimum Payments, Due - 2017	96
Operating Leases, Future Minimum Payments, Due Thereafter	196
Operating Leases, Future Minimum Payments Due - Total	1,098
Operating Leases, Rent Expense, Net [Abstract]
Rental expense	510	540	611
Building [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	36 years
Machinery, equipment and other [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	14 years 6 months
Software [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Mainframe and client based software [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	8 years
Land Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	30 years
Automotive [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Net property	24,813	22,229
Depreciation, Depletion and Amortization [Abstract]
Depreciation and other amortization	1,794	1,759	1,956
Amortization of special tools	1,861	1,774	1,920
Total	3,655	3,533	3,876
Maintenance and rearrangement	1,352	1,431	1,397
Operating Leases, Future Minimum Payments Due [Abstract]
Operating Leases, Future Minimum Payments Due - 2013	217
Operating Leases, Future Minimum Payments, Due - 2014	189
Operating Leases, Future Minimum Payments, Due - 2015	144
Operating Leases, Future Minimum Payments, Due - 2016	98
Operating Leases, Future Minimum Payments, Due - 2017	74
Operating Leases, Future Minimum Payments, Due Thereafter	172
Operating Leases, Future Minimum Payments Due - Total	894
Operating Leases, Rent Expense, Net [Abstract]
Rental expense	404	416	475
Automotive [Member] | Land [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Gross property	423	384
Automotive [Member] | Buildings and Land Improvements [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Gross property	10,249	10,129
Automotive [Member] | Machinery, equipment and other [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Gross property	35,040	34,363
Automotive [Member] | Software [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Gross property	1,813	1,917
Automotive [Member] | Construction in progress [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Gross property	1,783	1,311
Automotive [Member] | Land, plant and equipment and other [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Gross property	49,308	48,104
Accumulated depreciation	(32,835)	(32,874)
Net property	16,473	15,230
Automotive [Member] | Special tools, net of amortization [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Net property	8,340	6,999
Financial Services [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Net property	129	142
Depreciation, Depletion and Amortization [Abstract]
Total	2,524	1,843	2,024
Operating Leases, Future Minimum Payments Due [Abstract]
Operating Leases, Future Minimum Payments Due - 2013	52
Operating Leases, Future Minimum Payments, Due - 2014	41
Operating Leases, Future Minimum Payments, Due - 2015	34
Operating Leases, Future Minimum Payments, Due - 2016	31
Operating Leases, Future Minimum Payments, Due - 2017	22
Operating Leases, Future Minimum Payments, Due Thereafter	24
Operating Leases, Future Minimum Payments Due - Total	204
Operating Leases, Rent Expense, Net [Abstract]
Rental expense	$ 106	$ 124	$ 136
Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	36 years