Income Taxes	9 Months Ended
Sep. 30, 2016
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company’s effective tax rate is 2% and 42% for the nine-month periods ended September 30, 2016 and 2015, respectively. The Company's effective tax rate differs from the statutory federal tax rate of 34% for the nine-month period ended September 30, 2016 primarily due to a full valuation allowance recorded on our United States deferred tax assets since we cannot anticipate when or if we will have sufficient taxable income to utilize the deferred tax assets in the future. Further, our effective tax rate differs from the statutory federal tax rate due to state taxes, differences between U.S. and foreign tax rates, foreign losses incurred with no related tax benefit, non-deductible commissions, and non-deductible meals and entertainment expenses for the three-month periods ended September 30, 2016 and 2015, respectively. Fuel Tech had unrecognized tax benefits of $37 and $140 as of September 30, 2016 and December 31, 2015 respectively, all of which, if ultimately recognized, will reduce Fuel Tech's annual effective tax rate. Effective beginning April 1, 2016, Fuel Tech prospectively adopted ASU 2015-17, "Balance Sheet Classification of Deferred Taxes" and as a result classified all deferred tax assets and liabilities as non-current.

Income Taxes

9 Months Ended

Sep. 30, 2016

The Company’s effective tax rate is 2% and 42% for the nine-month periods ended September 30, 2016 and 2015, respectively. The Company's effective tax rate differs from the statutory federal tax rate of 34% for the nine-month period ended September 30, 2016 primarily due to a full valuation allowance recorded on our United States deferred tax assets since we cannot anticipate when or if we will have sufficient taxable income to utilize the deferred tax assets in the future. Further, our effective tax rate differs from the statutory federal tax rate due to state taxes, differences between U.S. and foreign tax rates, foreign losses incurred with no related tax benefit, non-deductible commissions, and non-deductible meals and entertainment expenses for the three-month periods ended September 30, 2016 and 2015, respectively.

Fuel Tech had unrecognized tax benefits of $37 and $140 as of September 30, 2016 and December 31, 2015 respectively, all of which, if ultimately recognized, will reduce Fuel Tech's annual effective tax rate.

Effective beginning April 1, 2016, Fuel Tech prospectively adopted ASU 2015-17, "Balance Sheet Classification of Deferred Taxes" and as a result classified all deferred tax assets and liabilities as non-current.