Income Taxes	9 Months Ended
Sep. 30, 2014
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The provision for income taxes for the first nine months of 2014 reflects an estimated annual effective tax rate of 29.5 percent compared with 29 percent for the first nine months of 2013, excluding the items discussed below. The increase from the full-year 2013 rate of 28.5 percent is primarily due to the expiration of the U.S. research and development tax credit. The provision for income taxes for the first nine months of 2014 also includes a net benefit of $21 million to adjust prior years' U.S. taxes and interest. A $33 million benefit was recorded to reflect a settlement with the U.S. Internal Revenue Service (IRS) related to 1992 through 1994 which resulted in a $16 million benefit to remeasure previously unrecognized tax benefits and a $17 million benefit to adjust related interest, net of tax. This benefit was offset by a net charge of $12 million to adjust prior years' U.S. taxes that included a charge of $55 million to correct for an error which resulted in an understatement of tax liabilities for prior years. The provision for income taxes for the first nine months of 2013 also included a benefit of $87 million primarily related to the research and development tax credit that was retroactively extended for 2012 and a benefit of $55 million to adjust the prior year's U.S. taxes. It is reasonably possible that the amount of unrecognized tax benefits will change in the next 12 months. The IRS is currently examining our U.S. tax returns for 2007 to 2009 including the impact of a loss carryback to 2005. While we have not yet received a Revenue Agent's Report generally issued at the end of the field examination process, we have received Notices of Proposed Adjustment from the IRS relating to U.S. taxation of profits earned by one of our non-U.S. subsidiaries, Caterpillar SARL, from certain parts transactions and to the disallowance of foreign tax credits incurred in connection with unrelated financings. We disagree with these proposed adjustments, which the IRS did not propose in previous audits of U.S. tax returns in which the same tax positions were taken. To the extent that adjustments are assessed upon completion of the field examination relating to these matters, we would vigorously contest the adjustments in appeals. The completion of the field examination for this audit is expected in the next 12 months. In our major non-U.S. jurisdictions, tax years are typically subject to examination for three to eight years. In the opinion of management, the ultimate disposition of these matters will not have a material adverse effect on our consolidated financial position, liquidity or results of operations. Due to the uncertainty related to the timing and potential outcome of these matters, we cannot estimate the range of reasonably possible change in unrecognized tax benefits in the next 12 months.

Income Taxes

The provision for income taxes for the first nine months of 2014 reflects an estimated annual effective tax rate of 29.5 percent compared with 29 percent for the first nine months of 2013, excluding the items discussed below. The increase from the full-year 2013 rate of 28.5 percent is primarily due to the expiration of the U.S. research and development tax credit.

The provision for income taxes for the first nine months of 2014 also includes a net benefit of $21 million to adjust prior years' U.S. taxes and interest. A $33 million benefit was recorded to reflect a settlement with the U.S. Internal Revenue Service (IRS) related to 1992 through 1994 which resulted in a $16 million benefit to remeasure previously unrecognized tax benefits and a $17 million benefit to adjust related interest, net of tax. This benefit was offset by a net charge of $12 million to adjust prior years' U.S. taxes that included a charge of $55 million to correct for an error which resulted in an understatement of tax liabilities for prior years. The provision for income taxes for the first nine months of 2013 also included a benefit of $87 million primarily related to the research and development tax credit that was retroactively extended for 2012 and a benefit of $55 million to adjust the prior year's U.S. taxes.

It is reasonably possible that the amount of unrecognized tax benefits will change in the next 12 months. The IRS is currently examining our U.S. tax returns for 2007 to 2009 including the impact of a loss carryback to 2005. While we have not yet received a Revenue Agent's Report generally issued at the end of the field examination process, we have received Notices of Proposed Adjustment from the IRS relating to U.S. taxation of profits earned by one of our non-U.S. subsidiaries, Caterpillar SARL, from certain parts transactions and to the disallowance of foreign tax credits incurred in connection with unrelated financings. We disagree with these proposed adjustments, which the IRS did not propose in previous audits of U.S. tax returns in which the same tax positions were taken. To the extent that adjustments are assessed upon completion of the field examination relating to these matters, we would vigorously contest the adjustments in appeals. The completion of the field examination for this audit is expected in the next 12 months. In our major non-U.S. jurisdictions, tax years are typically subject to examination for three to eight years. In the opinion of management, the ultimate disposition of these matters will not have a material adverse effect on our consolidated financial position, liquidity or results of operations. Due to the uncertainty related to the timing and potential outcome of these matters, we cannot estimate the range of reasonably possible change in unrecognized tax benefits in the next 12 months.