Quarterly report pursuant to Section 13 or 15(d)

Income Taxes

Income Taxes
9 Months Ended
Sep. 30, 2018
Income Tax Disclosure [Abstract]  
Income Taxes
Income Taxes
We make estimates and judgments in determining our provision for income taxes for financial statement purposes. These estimates and judgments occur in the calculation of certain tax assets and liabilities that arise from differences in the timing of recognition of revenue and expense for tax and financial statement purposes.
Our provision for income taxes in interim periods is based on our estimated annual effective tax rate. We record cumulative adjustments in the quarter in which a change in the estimated annual effective rate is determined. The estimated annual effective tax rate calculation does not include the effect of discrete events that may occur during the year. The effect of these events, if any, is recorded in the quarter in which the event occurs.
On December 22, 2017, the Tax Cuts and Jobs Act (“Tax Reform Act”) was enacted into law which changed U.S. tax law, including, but not limited to: (1) reducing the U.S. federal corporate income tax rate from 35% to 21% (2) requiring companies to pay a one-time transition tax on certain unrepatriated earnings of foreign subsidiaries (3) generally eliminating U.S. federal corporate income taxes on dividends from foreign subsidiaries (4) capitalizing U.S. R&D expenses which are amortized over five years and (5) other changes affecting how foreign and domestic earnings are taxed. Due to the complexities involved in accounting for the enactment of the new law, the SEC issued Staff Accounting Bulletin No. 118 ("SAB 118") to address the application of US GAAP in situations where a registrant does not have the necessary information available, prepared, or analyzed (including computations) in reasonable detail to complete the accounting for certain income tax effects of the Tax Reform Act. At December 31, 2017, we recorded provisional estimates in accordance with SAB 118, including a provisional determination of the impact of the change in corporate tax rates on our deferred tax balances, and a provisional estimate of the amount of transition tax associated with the mandatory deemed repatriation of foreign earnings. We did not make any changes to our provisional estimates during the quarter ended September 30, 2018. We will continue to analyze the impact of the Tax Reform Act as additional guidance is provided by the IRS and state taxing authorities. Additional impacts will be recorded as they are identified during the measurement period provided for in SAB 118.
The Tax Reform Act includes a provision to tax global intangible low-taxed income (“GILTI”) of foreign subsidiaries and a base erosion anti-abuse tax (“BEAT”) measure that taxes certain payments between a U.S. corporation and its foreign subsidiaries. These provisions of the Tax Reform Act were effective for the Company beginning January 1, 2018. The FASB Staff Q&A, Topic 740, No. 5, Accounting for Global Intangible Low-Taxed Income, states that an entity can make an accounting policy election to either recognize deferred taxes for temporary differences expected to reverse as GILTI in future years or provide for the tax expense related to GILTI in the year the tax is incurred as a period expense only. At September 30, 2018, we elected to treat GILTI as a period expense. At September 30, 2018, we have included GILTI related to current year operations only in our estimated annual effective tax rate and have not provided additional GILTI on deferred items.
Our effective income tax rate was 0.7% and (82.4)% for the nine months ended September 30, 2018 and 2017, respectively. Our effective rate is lower than the statutory rate for the nine months ended September 30, 2018 and 2017, primarily because of excess tax benefits from stock-based compensation of $10.1 million and $14.4 million, respectively, recognized as discrete items, as required by ASU 2016-09.
As a result of our adoption of ASU 2014-09, on January 1, 2018, we recorded a net deferred tax liability of $0.8 million, with a corresponding increase to accumulated deficit.