Guarantees and Product Warranty (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Commitments and Contingencies Disclosure [Abstract]
Related liability	$ 15	$ 7
Guarantor Obligations
Guarantees, maximum potential amount of future payments	400	365
Financial Special-Purpose Company's assets in Consolidated Statement of Financial Position	866	586
Financial Special-Purpose Company's liabilities in Consolidated Statement of Financial Position	866	586
Caterpillar dealer guarantees
Guarantor Obligations
Guarantees, maximum potential amount of future payments	146	140
Customer guarantees
Guarantor Obligations
Guarantees, maximum potential amount of future payments	180	186
Limited idemnity
Guarantor Obligations
Guarantees, maximum potential amount of future payments	8	11
Other guarantees
Guarantor Obligations
Guarantees, maximum potential amount of future payments	$ 66	$ 28