Income Taxes	3 Months Ended
Mar. 31, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Effective Income Tax Rate and Income Tax Provision On December 22, 2017, the TCJA was enacted into law. TCJA significantly changes existing U.S. tax law and includes numerous provisions that affect our business such as imposing a one-time transition tax on deemed repatriation of deferred foreign income ("Transition Tax"), reducing the U.S. federal statutory tax rate, and adopting a territorial tax system. The TCJA includes a provision to tax global intangible low-taxed income (“GILTI”), thereby requiring us to include in our U.S income tax return foreign subsidiary earnings in excess of an allowable return on the foreign subsidiary’s tangible assets. The GILTI provision is complex and subject to continuing regulatory interpretation by the U.S. Internal Revenue Service (“IRS”). We are required to make an accounting policy election to either (1) treat taxes due on future U.S. inclusions in taxable income related to GILTI as a current period expense when incurred (the “period cost method”) or (2) factor such amounts into the Company’s measurement of its deferred taxes (the “deferred method”). We have elected to recognize the GILTI as a period expense in the period the tax is incurred. Under this policy, we have not provided deferred taxes related to temporary differences that upon their reversal will affect the amount of income subject to GILTI in the period. For interim tax reporting, we estimate one annual effective tax rate for tax jurisdictions not subject to a valuation allowance and apply that rate to the year-to-date ordinary income/(loss). Tax effects of significant unusual or infrequently occurring items are excluded from the estimated annual effective tax rate calculation and recognized in the interim period in which they occur. Our effective income tax rate was 32.1% for the three months ended March 31, 2019. In comparison to the U.S. statutory rate of 21.0%, the Company's effective income tax rate is negatively impacted by foreign earnings taxed at a higher rate, the effect of GILTI and other foreign income inclusions in the U.S. tax base, state income taxes and non-deductible expenses, and is positively impacted by the benefits of the research and development credit. Our effective income tax rate was 283.3% for the three months ended March 31, 2018. In comparison to the U.S. statutory rate of 21.0%, the Company's effective income tax rate was negatively impacted by the Transition Tax and GILTI provisions associated with the TCJA, non-deductible expenses and state income taxes. There was a negligible change in our valuation allowances for the three months ended March 31, 2019. We reported a net increase in unrecognized tax benefits in the three months ended March 31, 2019 of $2.0 million primarily related to interest accrual on existing positions. Interest and penalties on tax assessments are included in income tax expense.

Income Taxes

Effective Income Tax Rate and Income Tax Provision

On December 22, 2017, the TCJA was enacted into law. TCJA significantly changes existing U.S. tax law and includes numerous provisions that affect our business such as imposing a one-time transition tax on deemed repatriation of deferred foreign income ("Transition Tax"), reducing the U.S. federal statutory tax rate, and adopting a territorial tax system. The TCJA includes a provision to tax global intangible low-taxed income (“GILTI”), thereby requiring us to include in our U.S income tax return foreign subsidiary earnings in excess of an allowable return on the foreign subsidiary’s tangible assets. The GILTI provision is complex and subject to continuing regulatory interpretation by the U.S. Internal Revenue Service (“IRS”). We are required to make an accounting policy election to either (1) treat taxes due on future U.S. inclusions in taxable income related to GILTI as a current period expense when incurred (the “period cost method”) or (2) factor such amounts into the Company’s measurement of its deferred taxes (the “deferred method”). We have elected to recognize the GILTI as a period expense in the period the tax is incurred. Under this policy, we have not provided deferred taxes related to temporary differences that upon their reversal will affect the amount of income subject to GILTI in the period.

For interim tax reporting, we estimate one annual effective tax rate for tax jurisdictions not subject to a valuation allowance and apply that rate to the year-to-date ordinary income/(loss). Tax effects of significant unusual or infrequently occurring items are excluded from the estimated annual effective tax rate calculation and recognized in the interim period in which they occur.

Our effective income tax rate was 32.1% for the three months ended March 31, 2019. In comparison to the U.S. statutory rate of 21.0%, the Company's effective income tax rate is negatively impacted by foreign earnings taxed at a higher rate, the effect of GILTI and other foreign income inclusions in the U.S. tax base, state income taxes and non-deductible expenses, and is positively impacted by the benefits of the research and development credit.

Our effective income tax rate was 283.3% for the three months ended March 31, 2018. In comparison to the U.S. statutory rate of 21.0%, the Company's effective income tax rate was negatively impacted by the Transition Tax and GILTI provisions associated with the TCJA, non-deductible expenses and state income taxes.

There was a negligible change in our valuation allowances for the three months ended March 31, 2019.

We reported a net increase in unrecognized tax benefits in the three months ended March 31, 2019 of $2.0 million primarily related to interest accrual on existing positions. Interest and penalties on tax assessments are included in income tax expense.