6. Income Taxes	6 Months Ended
Jun. 30, 2017
Income Tax Disclosure [Abstract]
Income Taxes	We have adopted the provisions of accounting standard update (ASU) 2016-09 as of the beginning of the current fiscal year, which requires recognition through opening retained earnings of any pre-adoption date net operating loss (NOL) carryforwards from nonqualified stock options for excess tax benefits that were not previously recognized because the related tax deduction had not reduced taxes payable and other employee share-based payments, as well as recognition of all income tax effects from share-based payments arising on or after January 1, 2017 (our adoption date) in income tax expense. As a result, we recognized through opening retained earnings $1.3 million of pre-adoption date NOL carryforwards with remaining carryforward periods of more than 10 years (the corresponding deferred tax asset is $457 thousand). We recorded a full valuation allowance for this deferred tax asset. In addition, we realized shortfall tax expense of $19 thousand during the three months ended June 30, 2017 and windfall tax benefits of $2 thousand during the three months ended March 31, 2017, which we recognized as discrete period income tax and benefit, respectively, as required by the ASU. During the three and six months ended June 30, 2017, the Company’s effective income tax rate was 0%. The projected annual effective tax rate is less than the Federal statutory rate of 34%, primarily due to the change in the valuation allowance, as well as changes to estimated taxable income for 2017 and permanent differences. For the three and six months ended June 30, 2016, the Company’s effective income tax rate was 0%. There was no income tax expense for the three and six months ended June 30, 2017 or June 30, 2016. The Company provides for recognition of deferred tax assets if the realization of such assets is more likely than not to occur in accordance with accounting standards that address income taxes. Significant management judgment is required in determining the period in which the reversal of a valuation allowance should occur. The Company has considered all available evidence, both positive and negative, such as historical levels of income and future forecasts of taxable income amongst other items, in determining its valuation allowance. In addition, the Company’s assessment requires us to schedule future taxable income in accordance with accounting standards that address income taxes to assess the appropriateness of a valuation allowance which further requires the exercise of significant management judgment. The Company believes that the accounting estimate for the valuation of deferred tax assets is a critical accounting estimate, because judgment is required in assessing the likely future tax consequences of events that have been recognized in our financial statements or tax returns. The Company based the estimate of deferred tax assets and liabilities on current tax laws and rates and, in certain cases, business plans and other expectations about future outcomes. In the event that actual results differ from these estimates or the Company adjusts these estimates in future periods, the Company may need to adjust the recorded valuation allowance, which could materially impact our financial position and results of operations. The Company has recorded a full valuation allowance at June 30, 2017 and December 31, 2016 for its deferred tax assets. The valuation allowance was $19.1 million at June 30, 2017 and $18.6 million at December 31, 2016. We will continue to evaluate the ability to realize our deferred tax assets and related valuation allowance on a quarterly basis.

6. Income Taxes

6 Months Ended

Jun. 30, 2017

We have adopted the provisions of accounting standard update (ASU) 2016-09 as of the beginning of the current fiscal year, which requires recognition through opening retained earnings of any pre-adoption date net operating loss (NOL) carryforwards from nonqualified stock options for excess tax benefits that were not previously recognized because the related tax deduction had not reduced taxes payable and other employee share-based payments, as well as recognition of all income tax effects from share-based payments arising on or after January 1, 2017 (our adoption date) in income tax expense. As a result, we recognized through opening retained earnings $1.3 million of pre-adoption date NOL carryforwards with remaining carryforward periods of more than 10 years (the corresponding deferred tax asset is $457 thousand). We recorded a full valuation allowance for this deferred tax asset. In addition, we realized shortfall tax expense of $19 thousand during the three months ended June 30, 2017 and windfall tax benefits of $2 thousand during the three months ended March 31, 2017, which we recognized as discrete period income tax and benefit, respectively, as required by the ASU.

During the three and six months ended June 30, 2017, the Company’s effective income tax rate was 0%. The projected annual effective tax rate is less than the Federal statutory rate of 34%, primarily due to the change in the valuation allowance, as well as changes to estimated taxable income for 2017 and permanent differences. For the three and six months ended June 30, 2016, the Company’s effective income tax rate was 0%. There was no income tax expense for the three and six months ended June 30, 2017 or June 30, 2016.

The Company provides for recognition of deferred tax assets if the realization of such assets is more likely than not to occur in accordance with accounting standards that address income taxes. Significant management judgment is required in determining the period in which the reversal of a valuation allowance should occur. The Company has considered all available evidence, both positive and negative, such as historical levels of income and future forecasts of taxable income amongst other items, in determining its valuation allowance. In addition, the Company’s assessment requires us to schedule future taxable income in accordance with accounting standards that address income taxes to assess the appropriateness of a valuation allowance which further requires the exercise of significant management judgment.

The Company believes that the accounting estimate for the valuation of deferred tax assets is a critical accounting estimate, because judgment is required in assessing the likely future tax consequences of events that have been recognized in our financial statements or tax returns. The Company based the estimate of deferred tax assets and liabilities on current tax laws and rates and, in certain cases, business plans and other expectations about future outcomes. In the event that actual results differ from these estimates or the Company adjusts these estimates in future periods, the Company may need to adjust the recorded valuation allowance, which could materially impact our financial position and results of operations. The Company has recorded a full valuation allowance at June 30, 2017 and December 31, 2016 for its deferred tax assets. The valuation allowance was $19.1 million at June 30, 2017 and $18.6 million at December 31, 2016. We will continue to evaluate the ability to realize our deferred tax assets and related valuation allowance on a quarterly basis.