Debt Financing	6 Months Ended
Jun. 30, 2019
Debt Disclosure [Abstract]
Debt Financing	Debt Financing On June 19, 2019, the Company entered into a Cash Collateral Security agreement with BMO Harris Bank, N.A. (the BMO Harris agreement) to use for the sole purpose of issuing standby letters of credit. The BMO Harris agreement requires us to pledge as cash collateral 105% of the aggregate face amount of outstanding standby letters of credit. The Company pays 250 basis points on the face values of outstanding letters of credit. There are no financial covenants set forth in the BMO Harris agreement. At June 30, 2019, the Company had outstanding standby letters of credit totaling approximately $463 under the BMO Harris agreement. As of June 30, 2019, the Company held $502 in a separate restricted use designated BMO Harris Bank N.A. deposit account. In connection with the transition to BMO Harris Bank N.A., the Company entered into an amendment under its U.S. Domestic credit facility (the Facility) with JPMorgan Chase Bank, N.A. (JPM Chase) to reduce the maximum revolving credit borrowings from $5,500 to $2,750 and extended the maturity to December 31, 2019. Fuel Tech maintains the use of this Facility for its existing standby letters of credit. The Company intends to transition its existing letters of credit from JPM Chase to BMO Harris Bank, N.A. and not renew the Facility upon its maturity. The Facility is secured by $2,750 in cash held by the Company in a separate restricted use designated JPM Chase deposit account and has the Company’s Italian subsidiary, Fuel Tech S.r.l., as a guarantor. Outstanding borrowings under the Facility bear interest at a rate of LIBOR plus 300 basis points. There are no financial covenants set forth in this amendment to the Facility. As of June 30, 2019 and December 31, 2018, there were no outstanding borrowings on the credit facility. At June 30, 2019 and December 31, 2018, the Company had outstanding standby letters of credit and bank guarantees totaling approximately $2,550 and $5,028, respectively, under the Facility in connection with contracts in process. Fuel Tech is committed to reimbursing the issuing bank for any payments made by the bank under these instruments. At June 30, 2019 and December 31, 2018, approximately $200 and $443 was available for future borrowings under the Facility. In the event of default on the JPM Chase domestic facility, the cross default feature in each allows the lending bank to accelerate the payments of any amounts outstanding and may, under certain circumstances, allow the bank to cancel the facility. If the Company were unable to obtain a waiver for a breach of covenant and the bank accelerated the payment of any outstanding amounts, such acceleration may cause the Company’s cash position to deteriorate or, if cash on hand were insufficient to satisfy the payment due, may require the Company to obtain alternate financing to satisfy the accelerated payment.

Debt Financing

On June 19, 2019, the Company entered into a Cash Collateral Security agreement with BMO Harris Bank, N.A. (the BMO Harris agreement) to use for the sole purpose of issuing standby letters of credit. The BMO Harris agreement requires us to pledge as cash collateral 105% of the aggregate face amount of outstanding standby letters of credit. The Company pays 250 basis points on the face values of outstanding letters of credit. There are no financial covenants set forth in the BMO Harris agreement. At June 30, 2019, the Company had outstanding standby letters of credit totaling approximately $463 under the BMO Harris agreement. As of June 30, 2019, the Company held $502 in a separate restricted use designated BMO Harris Bank N.A. deposit account.

In connection with the transition to BMO Harris Bank N.A., the Company entered into an amendment under its U.S. Domestic credit facility (the Facility) with JPMorgan Chase Bank, N.A. (JPM Chase) to reduce the maximum revolving credit borrowings from $5,500 to $2,750 and extended the maturity to December 31, 2019. Fuel Tech maintains the use of this Facility for its existing standby letters of credit. The Company intends to transition its existing letters of credit from JPM Chase to BMO Harris Bank, N.A. and not renew the Facility upon its maturity. The Facility is secured by $2,750 in cash held by the Company in a separate restricted use designated JPM Chase deposit account and has the Company’s Italian subsidiary, Fuel Tech S.r.l., as a guarantor. Outstanding borrowings under the Facility bear interest at a rate of LIBOR plus 300 basis points. There are no financial covenants set forth in this amendment to the Facility. As of June 30, 2019 and December 31, 2018, there were no outstanding borrowings on the credit facility.

At June 30, 2019 and December 31, 2018, the Company had outstanding standby letters of credit and bank guarantees totaling approximately $2,550 and $5,028, respectively, under the Facility in connection with contracts in process. Fuel Tech is committed to reimbursing the issuing bank for any payments made by the bank under these instruments. At June 30, 2019 and December 31, 2018, approximately $200 and $443 was available for future borrowings under the Facility.

In the event of default on the JPM Chase domestic facility, the cross default feature in each allows the lending bank to accelerate the payments of any amounts outstanding and may, under certain circumstances, allow the bank to cancel the facility. If the Company were unable to obtain a waiver for a breach of covenant and the bank accelerated the payment of any outstanding amounts, such acceleration may cause the Company’s cash position to deteriorate or, if cash on hand were insufficient to satisfy the payment due, may require the Company to obtain alternate financing to satisfy the accelerated payment.