Income Taxes	3 Months Ended
Mar. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	8. Income Taxes The Company accounts for income taxes under the liability method in accordance with the provisions of ASC Topic 740, Income Taxes. The Company recognizes future tax benefits, such as net operating losses, to the extent those benefits are expected to be realized in future periods. Due to uncertainty surrounding the realization of its deferred tax assets, the Company has recorded a valuation allowance against its net deferred tax assets. The Company experienced a change in ownership as defined under Section 382 of the U.S. Internal Revenue Code in August 2011. As a result, the future use of its net operating losses and credit equivalents is currently limited to approximately $218.7 million for 2017. Any available but unused amounts will become available for use in all successive years, subject to certain limitations. Utilization of these net operating loss carryforwards would require the Company to generate future taxable income prior to their expiration. Furthermore, the utilization of the net operating loss carryforwards could be limited beyond the Company's generation of taxable income if an additional change in the underlying ownership of the Company's common stock has occurred, resulting in a limitation on the amounts that could be utilized in any given period under Section 382 of the Code.

Income Taxes

3 Months Ended

Mar. 31, 2017

8. Income Taxes

The Company accounts for income taxes under the liability method in accordance with the provisions of ASC Topic 740, Income Taxes. The Company recognizes future tax benefits, such as net operating losses, to the extent those benefits are expected to be realized in future periods. Due to uncertainty surrounding the realization of its deferred tax assets, the Company has recorded a valuation allowance against its net deferred tax assets. The Company experienced a change in ownership as defined under Section 382 of the U.S. Internal Revenue Code in August 2011. As a result, the future use of its net operating losses and credit equivalents is currently limited to approximately $218.7 million for 2017. Any available but unused amounts will become available for use in all successive years, subject to certain limitations. Utilization of these net operating loss carryforwards would require the Company to generate future taxable income prior to their expiration. Furthermore, the utilization of the net operating loss carryforwards could be limited beyond the Company's generation of taxable income if an additional change in the underlying ownership of the Company's common stock has occurred, resulting in a limitation on the amounts that could be utilized in any given period under Section 382 of the Code.