Contingencies	9 Months Ended
Sep. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Contingencies	Contingencies Fuel Tech is subject to various claims and contingencies related to, among other things, workers compensation, general liability (including product liability), and lawsuits. The Company records liabilities where a contingent loss is probable and can be reasonably estimated. If the reasonable estimate of a probable loss is a range, the Company records the most probable estimate of the loss or the minimum amount when no amount within the range is a better estimate than any other amount. The Company discloses a contingent liability even if the liability is not probable or the amount is not estimable, or both, if there is a reasonable possibility that a material loss may have been incurred. During the fourth quarter of 2017, the Company was notified that, on a project for which the Company served as a subcontractor to a prime contractor, the prime contractor had received notice from the end-user customer in China of its intent to deduct from final payment for the project liquidated damages in the amount of approximately $920 due to delays in project completion. Thus far, the prime contractor is working to resolve this matter without resorting to litigation. Nevertheless, the matter is in the preliminary stage and we cannot predict the ultimate outcome of this claim or estimate a range of possible losses related to this matter at this time. We intend to pursue all of our rights should the current negotiations not result in a satisfactory resolution of this matter. Fuel Tech issues a standard product warranty with the sale of its products to customers. Our recognition of warranty liability is based primarily on analyses of warranty claims experienced in the preceding years as the nature of our historical product sales for which we offer a warranty are substantially unchanged. This approach provides an aggregate warranty accrual that is historically aligned with actual warranty claims experienced. There was no change in the warranty liability balance during the nine-months ended September 30, 2018 and 2017. The warranty liability balance was $159 at September 30, 2018 and 2017.

Contingencies

Fuel Tech is subject to various claims and contingencies related to, among other things, workers compensation, general liability (including product liability), and lawsuits. The Company records liabilities where a contingent loss is probable and can be reasonably estimated. If the reasonable estimate of a probable loss is a range, the Company records the most probable estimate of the loss or the minimum amount when no amount within the range is a better estimate than any other amount. The Company discloses a contingent liability even if the liability is not probable or the amount is not estimable, or both, if there is a reasonable possibility that a material loss may have been incurred.

During the fourth quarter of 2017, the Company was notified that, on a project for which the Company served as a subcontractor to a prime contractor, the prime contractor had received notice from the end-user customer in China of its intent to deduct from final payment for the project liquidated damages in the amount of approximately $920 due to delays in project completion. Thus far, the prime contractor is working to resolve this matter without resorting to litigation. Nevertheless, the matter is in the preliminary stage and we cannot predict the ultimate outcome of this claim or estimate a range of possible losses related to this matter at this time. We intend to pursue all of our rights should the current negotiations not result in a satisfactory resolution of this matter.

Fuel Tech issues a standard product warranty with the sale of its products to customers. Our recognition of warranty liability is based primarily on analyses of warranty claims experienced in the preceding years as the nature of our historical product sales for which we offer a warranty are substantially unchanged. This approach provides an aggregate warranty accrual that is historically aligned with actual warranty claims experienced.

There was no change in the warranty liability balance during the nine-months ended September 30, 2018 and 2017. The warranty liability balance was $159 at September 30, 2018 and 2017.