Guarantees and Product Warranty (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Guarantees and Product Warranty
Related liability	$ 7	$ 7
Guarantor Obligations
Guarantees, maximum potential amount of future payments	346	365
Financial Special-Purpose Company's assets in Consolidated Statement of Financial Position	660	586
Financial Special-Purpose Company's liabilities in Consolidated Statement of Financial Position	660	586
Caterpillar dealer guarantees
Guarantor Obligations
Guarantees, maximum potential amount of future payments	121	140
Customer guarantees
Guarantor Obligations
Guarantees, maximum potential amount of future payments	187	186
Limited indemnity
Guarantor Obligations
Guarantees, maximum potential amount of future payments	10	11
Other guarantees
Guarantor Obligations
Guarantees, maximum potential amount of future payments	$ 28	$ 28