Income Taxes	6 Months Ended
Jun. 30, 2017
Income Tax Disclosure [Abstract]
Income Taxes	Income taxes The provision for income taxes for the first six months of 2017 reflects an estimated annual tax rate of 32 percent, which excludes the discrete items discussed in the following paragraph, compared to 25 percent for the first six months of 2016. The increase is primarily due to higher non-U.S. restructuring costs in 2017 that are taxed at relatively lower non-U.S. tax rates along with other changes in the geographic mix of profits from a tax perspective. Under the terms of a manufacturing service agreement, Caterpillar SARL (CSARL) will bear substantially all of the restructuring costs related to the closure of our Gosselies, Belgium, facility, reducing CSARL's profits taxable in Switzerland. In addition during the first six months of 2017, a tax benefit of $27 million was recorded for the settlement of stock-based compensation awards with tax deductions in excess of cumulative U.S. GAAP compensation expense. This benefit was partially offset by a $15 million increase to prior year taxes related to the Gosselies, Belgium, facility, restructuring costs. In January 2015, we received a Revenue Agent's Report from the Internal Revenue Service (IRS) indicating the end of the field examination of our U.S. income tax returns for 2007 to 2009 including the impact of a loss carryback to 2005. The IRS field examination for 2010 to 2012 that began in 2015 is expected to be completed in 2017. In November 2016, we received notices of proposed adjustments from the IRS for the 2010 to 2012 exam. In both these audits, the IRS has proposed to tax in the United States profits earned from certain parts transactions by CSARL, based on the IRS examination team's application of the "substance-over-form" or "assignment-of-income" judicial doctrines. We are vigorously contesting the proposed increases to tax and penalties for these years of approximately $2 billion. We believe that the relevant transactions complied with applicable tax laws and did not violate judicial doctrines. We have filed U.S. income tax returns on this same basis for years after 2012. Based on the information currently available, we do not anticipate a significant increase or decrease to our unrecognized tax benefits for this matter within the next 12 months. We currently believe the ultimate disposition of this matter will not have a material adverse effect on our consolidated financial position, liquidity or results of operations. Due to better than previously forecasted 2017 U.S. GAAP results in certain U.S. state jurisdictions, it is reasonably possible the valuation allowance for U.S. state deferred tax assets will decrease in the next twelve months.

Income taxes

The provision for income taxes for the first six months of 2017 reflects an estimated annual tax rate of 32 percent, which excludes the discrete items discussed in the following paragraph, compared to 25 percent for the first six months of 2016. The increase is primarily due to higher non-U.S. restructuring costs in 2017 that are taxed at relatively lower non-U.S. tax rates along with other changes in the geographic mix of profits from a tax perspective. Under the terms of a manufacturing service agreement, Caterpillar SARL (CSARL) will bear substantially all of the restructuring costs related to the closure of our Gosselies, Belgium, facility, reducing CSARL's profits taxable in Switzerland.

In addition during the first six months of 2017, a tax benefit of $27 million was recorded for the settlement of stock-based compensation awards with tax deductions in excess of cumulative U.S. GAAP compensation expense. This benefit was partially offset by a $15 million increase to prior year taxes related to the Gosselies, Belgium, facility, restructuring costs.

In January 2015, we received a Revenue Agent's Report from the Internal Revenue Service (IRS) indicating the end of the field examination of our U.S. income tax returns for 2007 to 2009 including the impact of a loss carryback to 2005. The IRS field examination for 2010 to 2012 that began in 2015 is expected to be completed in 2017. In November 2016, we received notices of proposed adjustments from the IRS for the 2010 to 2012 exam. In both these audits, the IRS has proposed to tax in the United States profits earned from certain parts transactions by CSARL, based on the IRS examination team's application of the "substance-over-form" or "assignment-of-income" judicial doctrines. We are vigorously contesting the proposed increases to tax and penalties for these years of approximately $2 billion. We believe that the relevant transactions complied with applicable tax laws and did not violate judicial doctrines. We have filed U.S. income tax returns on this same basis for years after 2012. Based on the information currently available, we do not anticipate a significant increase or decrease to our unrecognized tax benefits for this matter within the next 12 months. We currently believe the ultimate disposition of this matter will not have a material adverse effect on our consolidated financial position, liquidity or results of operations.

Due to better than previously forecasted 2017 U.S. GAAP results in certain U.S. state jurisdictions, it is reasonably possible the valuation allowance for U.S. state deferred tax assets will decrease in the next twelve months.