Investments in Unconsolidated Affiliated Companies (Details) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Investments in Unconsolidated Affiliated Companies
Reporting period lag for Combining financial information of unconsolidated affiliated companies (in months)			3 months or less
Results of Operations of unconsolidated affiliated companies:
Sales	$ 241	$ 202	$ 439	$ 364
Cost of sales	198	154	359	274
Gross profit	43	48	80	90
Profit (loss)	(17)		(34)	(2)
Assets:
Current assets	411		411		414
Property, plant and equipment - net	181		181		196
Other assets	39		39		39
Assets	631		631		649
Liabilities:
Current liabilities	316		316		274
Long-term debt due after one year	51		51		72
Other liabilities	38		38		40
Liabilities	405		405		386
Equity	226		226		263
Caterpillar's investments in unconsolidated affiliated companies:
Investments in equity method companies	103		103		135
Plus: Investments in cost method companies	20		20		29
Total investments in unconsolidated affiliated companies	$ 123		$ 123		$ 164

This item represents the disclosure of summarized financial information for unconsolidated subsidiaries and 50 percent-or-less owned entities accounted for using the equity method of accounting. If investments in common stock of corporate joint ventures or other investments accounted for under the equity method are, in the aggregate, material in relation to the financial position or results of operations of an investor, it may be necessary to present summarized information as to liabilities of the investee, or group of investments for which combined disclosure is appropriate, either by individual financial statement caption or in groups, as appropriate. This element represents long-term debt.

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