Segment Information (Details 3) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Reconciliation of Consolidated profit (loss) before taxes
Total profit from reportable segments	$ 2,323	$ 1,833
All other operating segments	218	245
Cost centers	34	21
Corporate costs	(360)	(271)
Timing	(151)	(76)
Methodology differences:
Inventory/cost of sales	(14)	6
Postretirement benefit expense	(186)	(192)
Financing costs	(115)	(89)
Equity in profit of unconsolidated affiliated companies	(2)	8
Currency	131	18
Interest rate swap		(25)
Other income/expense methodology differences	(61)	(59)
Other methodology differences	3	1
Consolidated profit before taxes	2,298	1,763
Reportable segments
Reconciliation of Consolidated profit (loss) before taxes
Total profit from reportable segments	2,801	2,176
Machinery and Power Systems
Reconciliation of Consolidated profit (loss) before taxes
All other operating segments	218	245
Cost centers	34	21
Corporate costs	(360)	(271)
Timing	(151)	(76)
Methodology differences:
Inventory/cost of sales	(14)	6
Postretirement benefit expense	(186)	(192)
Financing costs	(115)	(89)
Equity in profit of unconsolidated affiliated companies	(2)	8
Currency	131	18
Interest rate swap		(25)
Other income/expense methodology differences	(61)	(59)
Other methodology differences	2	(1)
Consolidated profit before taxes	2,092	1,625
Machinery and Power Systems | Reportable segments
Reconciliation of Consolidated profit (loss) before taxes
Total profit from reportable segments	2,596	2,040
Financial Products
Methodology differences:
Other methodology differences	1	2
Consolidated profit before taxes	206	138
Financial Products | Reportable segments
Reconciliation of Consolidated profit (loss) before taxes
Total profit from reportable segments	$ 205	$ 136