Acquisitions (Details) In Millions, except Share data in Billions, unless otherwise specified	3 Months Ended		9 Months Ended			1 Months Ended				3 Months Ended
	Sep. 30, 2013 USD ($)	Sep. 30, 2012 USD ($)	Sep. 30, 2013 USD ($)	Sep. 30, 2012 USD ($)	Dec. 31, 2012 USD ($)	Sep. 30, 2013 Johan Walter Berg AB USD ($)	Sep. 30, 2013 Johan Walter Berg AB EUR (€)	May 31, 2013 ERA Mining Machinery Limited (Siwei) USD ($) parties director	May 31, 2012 ERA Mining Machinery Limited (Siwei) USD ($) types	Dec. 31, 2012 ERA Mining Machinery Limited (Siwei) USD ($)	Oct. 31, 2012 ERA Mining Machinery Limited (Siwei)	May 31, 2012 Cash consideration ERA Mining Machinery Limited (Siwei) HKD	May 31, 2012 Loan note consideration ERA Mining Machinery Limited (Siwei) HKD
Acquisitions
Percentage of equity acquired (as a percent)						100.00%	100.00%		99.00%		1.00%
Purchase price of acquired entity						$ 166			$ 677
Cost of acquisition paid in cash									475	7
Net cash paid for acquisition			193	542					444
Fair value of loan notes debt component								152	152
Loan and interest payable to Caterpillar									51
Fair value of noncontrolling interest									7
Contingent consideration arrangements
Contingent consideration payable						7
Contingent consideration arrangement, maximum value (in Euro)							30
Number of consideration alternatives									2
Value of consideration to be paid (in HKD/share)												0.88	1.00
Contingent consideration arrangement, minimum value (in HKD/share)													0.75
Contingent consideration arrangement, maximum value (in HKD/share)													1.15
Number of shares tendered (in billions of shares)												4.0	1.6
Assets acquired
Tangible assets acquired						83			598
Cash						9			31
Restricted cash									138
Receivables						13			184
Inventories						33			77
Property, plant and equipment						28			94
Finite-lived intangible assets						66			112
Finite-lived intangible assets weighted average amortization period (in years)						10 years	10 years		14 years
Liabilities assumed
Total liabilities assumed						83			626
Accounts payable						19			352
Advance payments						33
Debt assumed									168
Accrued expenses									37
Net deferred tax liabilities						13			25
Goodwill	6,968		6,968		6,942	109			625	45
Adjustments to preliminary allocation of purchase price
Finite-lived intangibles decrease										82
Receivables decrease										29
Inventory decrease										17
Net liabilities increase										23
Goodwill increase										149
Goodwill impairment charge	0	0	0	0						580
Number of former directors								2
Number of other parties to the settlement								2
Payments by Caterpillar to parties of the settlement agreement								30
Obligation related to the loans by former directors								13
Gain related to settlement and discharge of loan obligations								$ 135