Income Taxes	3 Months Ended
Mar. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company is subject to income tax in the United States as well as other tax jurisdictions in which it conducts business. Earnings from non-U.S. activities are subject to local country income tax. For the three months ended March 31, 2018, the Company recorded a benefit for income taxes of $0.6 million, for an effective tax rate of 0.8%. The effective tax rate for the three months ended March 31, 2018, was different than the statutory federal tax rate primarily due to the impact of a full valuation allowance on the Company’s U.S. deferred tax assets. On December 22, 2017, the U.S. Tax Cuts and Jobs Act of 2017 (“2017 Tax Act”) was signed into law and includes several key tax provisions that affected the Company, including a reduction of the statutory corporate tax rate from 35% to 21% effective for tax years beginning after December 31, 2017, elimination of the carryback of net operating losses generated after December 31, 2017, and changes to how the United States imposes income tax on multinational corporations, among others. In December 2017, Staff Accounting Bulletin No. 118 (“SAB 118”) was issued to address U.S. GAAP application when 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 by the 2017 Tax Act. For the three months ended March 31, 2018, no changes have been made to the provisional amounts previously recorded. The Company will complete its analysis within the measurement period in accordance with SAB 118. For the three months ended April 1, 2017, the Company recorded a benefit for income taxes of $29.7 million for an effective tax rate of 33.1%. The effective tax rate for the three months ended April 1, 2017 was different than the statutory federal tax rate, primarily due to research and development credits, non-deductible stock-based compensation expense, unrecognized tax benefits, the foregone benefit of a permanent domestic production activities deduction in prior periods, and the mix of income between United States and foreign jurisdictions. The Company accounts for deferred taxes under ASC Topic 740, “Income Taxes” (“ASC 740”) which involves weighing positive and negative evidence concerning the realizability of the Company’s deferred tax assets in each jurisdiction. In evaluating its ability to realize the net deferred tax assets, the Company considered all available positive and negative evidence, including its past operating results and the forecast of future market growth, forecasted earnings, future taxable income, and prudent and feasible tax planning strategies. As of March 31, 2018, the Company maintains a full valuation allowance against all its U.S. deferred tax assets. No valuation allowance has been recorded against the Company’s foreign deferred tax assets. The Company will continue to assess the realizability of its deferred tax assets in each of the applicable jurisdictions going forward. As of March 31, 2018, the total amount of gross unrecognized tax benefits was $33.9 million, of which $25.3 million would affect the effective tax rate if recognized. The Company does not have any tax positions as of March 31, 2018 for which it is reasonably possible that the total amount of gross unrecognized tax benefits will increase or decrease within the following 12 months.

Income Taxes

The Company is subject to income tax in the United States as well as other tax jurisdictions in which it conducts business. Earnings from non-U.S. activities are subject to local country income tax.

For the three months ended March 31, 2018, the Company recorded a benefit for income taxes of $0.6 million, for an effective tax rate of 0.8%. The effective tax rate for the three months ended March 31, 2018, was different than the statutory federal tax rate primarily due to the impact of a full valuation allowance on the Company’s U.S. deferred tax assets.

On December 22, 2017, the U.S. Tax Cuts and Jobs Act of 2017 (“2017 Tax Act”) was signed into law and includes several key tax provisions that affected the Company, including a reduction of the statutory corporate tax rate from 35% to 21% effective for tax years beginning after December 31, 2017, elimination of the carryback of net operating losses generated after December 31, 2017, and changes to how the United States imposes income tax on multinational corporations, among others.

In December 2017, Staff Accounting Bulletin No. 118 (“SAB 118”) was issued to address U.S. GAAP application when 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 by the 2017 Tax Act. For the three months ended March 31, 2018, no changes have been made to the provisional amounts previously recorded. The Company will complete its analysis within the measurement period in accordance with SAB 118.

For the three months ended April 1, 2017, the Company recorded a benefit for income taxes of $29.7 million for an effective tax rate of 33.1%. The effective tax rate for the three months ended April 1, 2017 was different than the statutory federal tax rate, primarily due to research and development credits, non-deductible stock-based compensation expense, unrecognized tax benefits, the foregone benefit of a permanent domestic production activities deduction in prior periods, and the mix of income between United States and foreign jurisdictions.

The Company accounts for deferred taxes under ASC Topic 740, “Income Taxes” (“ASC 740”) which involves weighing positive and negative evidence concerning the realizability of the Company’s deferred tax assets in each jurisdiction. In evaluating its ability to realize the net deferred tax assets, the Company considered all available positive and negative evidence, including its past operating results and the forecast of future market growth, forecasted earnings, future taxable income, and prudent and feasible tax planning strategies. As of March 31, 2018, the Company maintains a full valuation allowance against all its U.S. deferred tax assets. No valuation allowance has been recorded against the Company’s foreign deferred tax assets. The Company will continue to assess the realizability of its deferred tax assets in each of the applicable jurisdictions going forward.

As of March 31, 2018, the total amount of gross unrecognized tax benefits was $33.9 million, of which $25.3 million would affect the effective tax rate if recognized. The Company does not have any tax positions as of March 31, 2018 for which it is reasonably possible that the total amount of gross unrecognized tax benefits will increase or decrease within the following 12 months.