Guarantees and Product Warranty (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012	Jul. 31, 2012
Commitments and Contingencies Disclosure [Abstract]
Percentage of equity interest sold in subsidiary (as a percent)			65.00%
Related liability	$ 16	$ 14
Guarantor Obligations
Guarantees, maximum potential amount of future payments	803	486
Financial Special-Purpose Company's assets in Consolidated Statement of Financial Position	804	927
Financial Special-Purpose Company's liabilities in Consolidated Statement of Financial Position	804	927
Caterpillar dealer guarantees
Guarantor Obligations
Guarantees, maximum potential amount of future payments	177	180
Customer guarantees
Guarantor Obligations
Guarantees, maximum potential amount of future payments	70	77
Customer guarantees-supplier consortium
Guarantor Obligations
Guarantees, maximum potential amount of future payments	341	0
Third party logistics business
Guarantor Obligations
Guarantees, maximum potential amount of future payments	170	176
Other guarantees
Guarantor Obligations
Guarantees, maximum potential amount of future payments	$ 45	$ 53