Debt Financing	3 Months Ended
Mar. 31, 2019
Debt Disclosure [Abstract]
Debt Financing	Debt Financing The Company is obligated under a U.S. Domestic credit facility with (the Facility) with JPMorgan Chase Bank, N.A. (JPM Chase) which provides for maximum revolving credit borrowings of $5,500 and matures on June 28, 2019. Fuel Tech can use this Facility for cash advances and standby letters of credit. The Facility is secured by $5,500 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. The Company is actively pursuing the renewal of its U.S. Domestic credit facility and intends to renew the U.S. Domestic credit facility at its maturity. As of March 31, 2019 and December 31, 2018, there were no outstanding borrowings on the credit facility. At March 31, 2019 and December 31, 2018, the Company had outstanding standby letters of credit and bank guarantees totaling approximately $5,255 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. The Company pays a commitment fee of 0.25% per year on the unused portion of the revolving credit facility. At March 31, 2019 and December 31, 2018, approximately $245 and $443 was available for future borrowings under the Facility. Beijing Fuel Tech Environmental Technologies Company, Ltd. (Beijing Fuel Tech), is obligated under a revolving credit facility (the China Facility) agreement with JPM Chase which provides for maximum revolving credit borrowings of RMB 2.625 million (approximately $391) and matures on June 30, 2019. The Facility is secured by $520 in cash held by the Company in a separate restricted use designated JPM Chase deposit account. The China Facility bears interest at a rate of 140% of the People’s Bank of China (PBOC) Base Rate, and is guaranteed by the Company. Beijing Fuel Tech can use this facility for cash advances and bank guarantees. As of March 31, 2019 and December 31, 2018, Beijing Fuel Tech had no cash borrowings under the China Facility. At March 31, 2019 and December 31, 2018, we had no outstanding standby letters of credit and bank guarantees on its Beijing Fuel Tech revolving credit facility in connection with contracts in process. At March 31, 2019 and December 31, 2018, approximately $391 and $382 was available for future borrowings. As a result of the announcement of the suspension of the Air Pollution Control business in Beijing, the Company intends to not renew the China Facility upon its expiration on June 30, 2019. In the event of default on either the domestic facility or the China 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

The Company is obligated under a U.S. Domestic credit facility with (the Facility) with JPMorgan Chase Bank, N.A. (JPM Chase) which provides for maximum revolving credit borrowings of $5,500 and matures on June 28, 2019. Fuel Tech can use this Facility for cash advances and standby letters of credit. The Facility is secured by $5,500 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. The Company is actively pursuing the renewal of its U.S. Domestic credit facility and intends to renew the U.S. Domestic credit facility at its maturity. As of March 31, 2019 and December 31, 2018, there were no outstanding borrowings on the credit facility.

At March 31, 2019 and December 31, 2018, the Company had outstanding standby letters of credit and bank guarantees totaling approximately $5,255 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. The Company pays a commitment fee of 0.25% per year on the unused portion of the revolving credit facility. At March 31, 2019 and December 31, 2018, approximately $245 and $443 was available for future borrowings under the Facility.

Beijing Fuel Tech Environmental Technologies Company, Ltd. (Beijing Fuel Tech), is obligated under a revolving credit facility (the China Facility) agreement with JPM Chase which provides for maximum revolving credit borrowings of RMB 2.625 million (approximately $391) and matures on June 30, 2019. The Facility is secured by $520 in cash held by the Company in a separate restricted use designated JPM Chase deposit account. The China Facility bears interest at a rate of 140% of the People’s Bank of China (PBOC) Base Rate, and is guaranteed by the Company. Beijing Fuel Tech can use this facility for cash advances and bank guarantees. As of March 31, 2019 and December 31, 2018, Beijing Fuel Tech had no cash borrowings under the China Facility. At March 31, 2019 and December 31, 2018, we had no outstanding standby letters of credit and bank guarantees on its Beijing Fuel Tech revolving credit facility in connection with contracts in process. At March 31, 2019 and December 31, 2018, approximately $391 and $382 was available for future borrowings. As a result of the announcement of the suspension of the Air Pollution Control business in Beijing, the Company intends to not renew the China Facility upon its expiration on June 30, 2019.

In the event of default on either the domestic facility or the China 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.