Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013 segments group_presidents	Mar. 31, 2012	Dec. 31, 2012
Reportable Segments
Number of group presidents	5
Number of operating segments led by Group Presidents	3
Number of operating segment led by Group president responsible for corporate services	1
Number of smaller operating segments led by Group President	1
Number of operating segments	5
Number of reportable segments	4
Useful life to amortize goodwill to segment assets	20 years
External sales and revenues	$ 13,210	$ 15,981
Depreciation and amortization	723	661
Segment profit	1,218	2,323
Segment assets	88,743		89,356
Capital expenditures	1,232	1,129
Reportable segments
Reportable Segments
External sales and revenues	13,073	15,588
Inter-segment sales and revenues	727	1,133
Total sales and revenues	13,800	16,721
Depreciation and amortization	649	606
Segment profit	1,587	2,801
Segment assets	68,147		69,734
Capital expenditures	655	735
Machinery and Power Systems
Reportable Segments
External sales and revenues	12,484	15,288
Depreciation and amortization	538	482
Segment assets	57,325		58,284
Capital expenditures	913	864
Machinery and Power Systems | Reportable segments
Reportable Segments
External sales and revenues	12,278	14,827
Inter-segment sales and revenues	727	1,133
Total sales and revenues	13,005	15,960
Depreciation and amortization	469	432
Segment profit	1,314	2,596
Segment assets	31,181		33,171
Capital expenditures	335	392
Construction Industries | Reportable segments
Reportable Segments
External sales and revenues	4,197	5,062
Inter-segment sales and revenues	111	130
Total sales and revenues	4,308	5,192
Depreciation and amortization	138	131
Segment profit	239	616
Segment assets	9,407		10,393
Capital expenditures	124	131
Resource Industries | Reportable segments
Reportable Segments
External sales and revenues	3,676	4,778
Inter-segment sales and revenues	220	328
Total sales and revenues	3,896	5,106
Depreciation and amortization	180	163
Segment profit	477	1,168
Segment assets	12,471		13,455
Capital expenditures	107	132
Power Systems | Reportable segments
Reportable Segments
External sales and revenues	4,405	4,987
Inter-segment sales and revenues	396	675
Total sales and revenues	4,801	5,662
Depreciation and amortization	151	138
Segment profit	598	812
Segment assets	9,303		9,323
Capital expenditures	104	129
Financial Products Segment | Reportable segments
Reportable Segments
External sales and revenues	795	761
Inter-segment sales and revenues	0	0
Total sales and revenues	795	761
Depreciation and amortization	180	174
Segment profit	273	205
Segment assets	36,966		36,563
Capital expenditures	$ 320	$ 343