Income Taxes	6 Months Ended
Jun. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES For the three months ended June 30, 2018, the Company recorded an income tax benefit of $3.3 million on a pretax loss of $31.6 million and for the six months ended June 30, 2018, the Company recorded an income tax benefit of $6.0 million on a pretax loss of $67.2 million, which resulted in an effective tax rate year to date of 8.9%. The income tax benefit for the three and six months ended June 30, 2018 was primarily related to tax benefit from losses and credits generated from operations offset by foreign withholding taxes, certain book-to-tax permanent differences, valuation allowance recorded against the Company’s unutilized tax credits generated in the current year, and shortfalls from stock-based compensation. For the three months ended June 30, 2017, the Company recorded an income tax provision of $26.6 million, and for the six months ended June 30, 2017, the Company recorded an income tax benefit of $8.7 million, which resulted in an effective tax rate year to date of 14.8%. The income tax provision of $26.6 million for the three months ended June 30, 2017 was primarily related to a decrease in the Company’s estimated annual effective tax rate applied to actual year-to-date losses incurred that resulted in a reduction of actual tax benefit as compared to the prior quarter. The income tax benefit of $8.7 million for the six months ended June 30, 2017 was primarily related to losses generated in the U.S. and foreign operations offset by foreign withholding tax liability. The Company's provision for income taxes is based on its worldwide estimated annualized effective tax rate, except for jurisdictions for which a loss is expected for the year and no benefit can be realized for those losses, and the tax effect of discrete items occurring during the period. The tax for jurisdictions for which a loss is expected and no benefit can be realized for the year is based on actual taxes and tax reserves for the quarter. The decrease in income tax benefit for the six months ended June 30, 2018 as compared to the income tax benefit during the same period in the prior year is largely attributable to valuation allowance recorded against the Company’s tax credits. As of June 30, 2018, unrecognized tax benefits were $34.1 million (which is included in long-term deferred tax and other liabilities on the Condensed Consolidated Balance Sheet), of which $22.2 million would affect the effective tax rate if recognized. As of June 30, 2017, unrecognized tax benefits were $30.5 million (which was included in long-term deferred tax and other liabilities on the Condensed Consolidated Balance Sheet), of which $24.0 million would affect the effective tax rate if recognized. The Company is unable to reasonably estimate the timing of the long-term payments or the amount by which the liability will increase or decrease. It is the Company's policy to classify accrued interest and penalties related to unrecognized tax benefits in the provision for income taxes. For the six months ended June 30, 2018 and June 30, 2017, the Company recognized an insignificant amount of interest and penalties related to unrecognized tax benefits. Accrued interest and penalties were $0.7 million and $0.6 million as of June 30, 2018 and December 31, 2017, respectively. At June 30, 2018, the Company's 2013 through 2017 tax years were open and subject to potential examination in one or more jurisdictions. In addition, in the U.S., any net operating losses or credits that were generated in prior years but not yet fully utilized in a year that is closed under the statute of limitations may also be subject to examination. The Company is currently under examination by the Internal Revenue Service for tax year 2014 and cannot estimate the financial outcome of the examination. The Company is not currently under foreign income tax examination. On December 22, 2017, the Tax Cut and Jobs Act (“Tax Act”) was signed into law. The Tax Act introduced a broad range of tax reform measures that significantly change the federal income tax laws. As of December 31, 2017, the Company recorded a provisional tax expense in the Statement of Operations of approximately $5.6 million, comprised of approximately $13.5 million tax expense from recording additional valuation allowance against federal tax credits due to certain provisions of the Tax Act, offset by approximately $7.9 million of tax benefit from the remeasurement of U.S. deferred taxes using the relevant tax rate at which the Company expects them to reverse in the future. The estimated one-time transition tax on post-1986 foreign unremitted earnings is not anticipated to have a material impact to the Company's effective tax rate. As of June 30, 2018, the Company has not recorded any adjustments to the provisional tax expense. The Company continues to monitor supplemental legislation and technical interpretations of the tax law that may cause the final impact from the Tax Act to differ from the provisionally recorded amounts. The Company expects to complete its analysis within the measurement period allowed by Staff Accounting Bulletin (“SAB”) No.118, no later than the fourth quarter of 2018.

INCOME TAXES

For the three months ended June 30, 2018, the Company recorded an income tax benefit of $3.3 million on a pretax loss of $31.6 million and for the six months ended June 30, 2018, the Company recorded an income tax benefit of $6.0 million on a pretax loss of $67.2 million, which resulted in an effective tax rate year to date of 8.9%. The income tax benefit for the three and six months ended June 30, 2018 was primarily related to tax benefit from losses and credits generated from operations offset by foreign withholding taxes, certain book-to-tax permanent differences, valuation allowance recorded against the Company’s unutilized tax credits generated in the current year, and shortfalls from stock-based compensation. For the three months ended June 30, 2017, the Company recorded an income tax provision of $26.6 million, and for the six months ended June 30, 2017, the Company recorded an income tax benefit of $8.7 million, which resulted in an effective tax rate year to date of 14.8%.

The income tax provision of $26.6 million for the three months ended June 30, 2017 was primarily related to a decrease in the Company’s estimated annual effective tax rate applied to actual year-to-date losses incurred that resulted in a reduction of actual tax benefit as compared to the prior quarter. The income tax benefit of $8.7 million for the six months ended June 30, 2017 was primarily related to losses generated in the U.S. and foreign operations offset by foreign withholding tax liability. The Company's provision for income taxes is based on its worldwide estimated annualized effective tax rate, except for jurisdictions for which a loss is expected for the year and no benefit can be realized for those losses, and the tax effect of discrete items occurring during the period. The tax for jurisdictions for which a loss is expected and no benefit can be realized for the year is based on actual taxes and tax reserves for the quarter. The decrease in income tax benefit for the six months ended June 30, 2018 as compared to the income tax benefit during the same period in the prior year is largely attributable to valuation allowance recorded against the Company’s tax credits.

As of June 30, 2018, unrecognized tax benefits were $34.1 million (which is included in long-term deferred tax and other liabilities on the Condensed Consolidated Balance Sheet), of which $22.2 million would affect the effective tax rate if recognized. As of June 30, 2017, unrecognized tax benefits were $30.5 million (which was included in long-term deferred tax and other liabilities on the Condensed Consolidated Balance Sheet), of which $24.0 million would affect the effective tax rate if recognized. The Company is unable to reasonably estimate the timing of the long-term payments or the amount by which the liability will increase or decrease.

It is the Company's policy to classify accrued interest and penalties related to unrecognized tax benefits in the provision for income taxes. For the six months ended June 30, 2018 and June 30, 2017, the Company recognized an insignificant amount of interest and penalties related to unrecognized tax benefits. Accrued interest and penalties were $0.7 million and $0.6 million as of June 30, 2018 and December 31, 2017, respectively.

At June 30, 2018, the Company's 2013 through 2017 tax years were open and subject to potential examination in one or more jurisdictions. In addition, in the U.S., any net operating losses or credits that were generated in prior years but not yet fully utilized in a year that is closed under the statute of limitations may also be subject to examination. The Company is currently under examination by the Internal Revenue Service for tax year 2014 and cannot estimate the financial outcome of the examination. The Company is not currently under foreign income tax examination.

On December 22, 2017, the Tax Cut and Jobs Act (“Tax Act”) was signed into law. The Tax Act introduced a broad range of tax reform measures that significantly change the federal income tax laws. As of December 31, 2017, the Company recorded a provisional tax expense in the Statement of Operations of approximately $5.6 million, comprised of approximately $13.5 million tax expense from recording additional valuation allowance against federal tax credits due to certain provisions of the Tax Act, offset by approximately $7.9 million of tax benefit from the remeasurement of U.S. deferred taxes using the relevant tax rate at which the Company expects them to reverse in the future. The estimated one-time transition tax on post-1986 foreign unremitted earnings is not anticipated to have a material impact to the Company's effective tax rate. As of June 30, 2018, the Company has not recorded any adjustments to the provisional tax expense. The Company continues to monitor supplemental legislation and technical interpretations of the tax law that may cause the final impact from the Tax Act to differ from the provisionally recorded amounts. The Company expects to complete its analysis within the measurement period allowed by Staff Accounting Bulletin (“SAB”) No.118, no later than the fourth quarter of 2018.