Income Taxes	3 Months Ended
Mar. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes For interim tax reporting we estimate our annual effective tax rate and apply it to our year to date ordinary income. Jurisdictions where no tax benefit can be recognized due to a valuation allowance are excluded from the estimated annual effective tax rate. The impact of including these jurisdictions on the quarterly effective rate calculation could result in a higher or lower effective tax rate during a particular quarter due to the mix and timing of actual earnings versus annual projections. The tax effects of certain unusual or infrequently occurring items, including changes in judgment about valuation allowances and effects of changes in tax laws or rates, are excluded from the estimated annual effective tax rate calculation and recognized in the interim period in which they occur. We reported income tax expense of $34 million in each of the three month periods ended March 31, 2017 and 2016. The tax expense recorded in the first quarter of 2017 included a net tax benefit of $1 million primarily relating to the first quarter 2017 adoption of Accounting Standard Update 2016-09, Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting. The tax expense recorded in the first quarter of 2016 included a net tax benefit of $3 million primarily relating to tax adjustments to uncertain tax positions and prior year income tax estimates. We believe it is reasonably possible that up to $17 million in unrecognized tax benefits related to the expiration of foreign statute of limitations and the conclusion of income tax examinations may be recognized within the next twelve months.

Income Taxes

3 Months Ended

Mar. 31, 2017

For interim tax reporting we estimate our annual effective tax rate and apply it to our year to date ordinary income. Jurisdictions where no tax benefit can be recognized due to a valuation allowance are excluded from the estimated annual effective tax rate. The impact of including these jurisdictions on the quarterly effective rate calculation could result in a higher or lower effective tax rate during a particular quarter due to the mix and timing of actual earnings versus annual projections. The tax effects of certain unusual or infrequently occurring items, including changes in judgment about valuation allowances and effects of changes in tax laws or rates, are excluded from the estimated annual effective tax rate calculation and recognized in the interim period in which they occur.

We reported income tax expense of $34 million in each of the three month periods ended March 31, 2017 and 2016. The tax expense recorded in the first quarter of 2017 included a net tax benefit of $1 million primarily relating to the first quarter 2017 adoption of Accounting Standard Update 2016-09, Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting. The tax expense recorded in the first quarter of 2016 included a net tax benefit of $3 million primarily relating to tax adjustments to uncertain tax positions and prior year income tax estimates.

We believe it is reasonably possible that up to $17 million in unrecognized tax benefits related to the expiration of foreign statute of limitations and the conclusion of income tax examinations may be recognized within the next twelve months.