Subsequent Events	9 Months Ended
Jul. 31, 2017
Subsequent Events [Abstract]
Subsequent Events	Note 17. Subsequent Events 20 Megawatt Order in South Korea On August 29, 2017, we entered into a contract to sell 20 megawatts of fuel cell power plants to Hanyang Industrial Development Company Ltd. (HYD), for installation at South Korean utility Korea Southern Power Company Ltd. (KOSPO). We expect that this project will represent in excess of $60 million of product revenue and any product not shipped by the end of the fourth fiscal quarter of 2017 will be added to backlog. Revenue for the fourth quarter of 2017 is expected to increase compared to the third quarter of 2017, as revenue begins to be recognized on this contract. Product revenue recognition will carry into fiscal year 2018. Convertible Preferred Offering On September 5, 2017, the Company priced an underwritten offering of 33,500 shares of convertible preferred stock (the “Series C Preferred”). The Series C Preferred carries a 0.0% dividend and a $1.84 conversion price. Each share of Series C Preferred is being sold at a price of $895.52 for gross proceeds of approximately $30 million. FuelCell Energy intends to use the net proceeds from this offering for working capital, project financing, and general corporate purposes. The offering closed on September 8, 2017. In connection with the convertible preferred offering, we have agreed with Hercules to amend the loan and security agreement (1) to permit us to make certain cash payments that may be required pursuant to the terms of the Series C Preferred Shares, (2) to require us to maintain an unrestricted blocked cash balance of at least the greater of (x) (a) $20.0 million plus (b) the amount of accounts payable not paid within 90 days of the date payment was issued and (y) (a) 100% of the outstanding loan balance plus (b) the amount of accounts payable not paid within 90 days of the date payment was issued and (3) to add an event of default in the event of the delivery of a notice by the holders to redeem the Series C Preferred Shares following a triggering event pursuant to the certificate of designations governing the Series C Preferred Shares. Proxy Ratification Vote On September 5, 2017, we filed a definitive proxy statement with the SEC which provides notice to our shareholders of a special meeting of shareholders to be held on Friday, September 29, 2017 to ratify the filing and effectiveness of the certificate of amendment to our amended and restated certificate of incorporation filed with the Secretary of State of the State of Delaware on December 3, 2015 and the 1-for-12 reverse stock split of our common stock that was effected thereby and became effective on December 3, 2015. 1

Note 17. Subsequent Events

20 Megawatt Order in South Korea

On August 29, 2017, we entered into a contract to sell 20 megawatts of fuel cell power plants to Hanyang Industrial Development Company Ltd. (HYD), for installation at South Korean utility Korea Southern Power Company Ltd. (KOSPO). We expect that this project will represent in excess of $60 million of product revenue and any product not shipped by the end of the fourth fiscal quarter of 2017 will be added to backlog. Revenue for the fourth quarter of 2017 is expected to increase compared to the third quarter of 2017, as revenue begins to be recognized on this contract. Product revenue recognition will carry into fiscal year 2018.

Convertible Preferred Offering

On September 5, 2017, the Company priced an underwritten offering of 33,500 shares of convertible preferred stock (the “Series C Preferred”). The Series C Preferred carries a 0.0% dividend and a $1.84 conversion price. Each share of Series C Preferred is being sold at a price of $895.52 for gross proceeds of approximately $30 million. FuelCell Energy intends to use the net proceeds from this offering for working capital, project financing, and general corporate purposes. The offering closed on September 8, 2017.

In connection with the convertible preferred offering, we have agreed with Hercules to amend the loan and security agreement (1) to permit us to make certain cash payments that may be required pursuant to the terms of the Series C Preferred Shares, (2) to require us to maintain an unrestricted blocked cash balance of at least the greater of (x) (a) $20.0 million plus (b) the amount of accounts payable not paid within 90 days of the date payment was issued and (y) (a) 100% of the outstanding loan balance plus (b) the amount of accounts payable not paid within 90 days of the date payment was issued and (3) to add an event of default in the event of the delivery of a notice by the holders to redeem the Series C Preferred Shares following a triggering event pursuant to the certificate of designations governing the Series C Preferred Shares.

Proxy Ratification Vote

On September 5, 2017, we filed a definitive proxy statement with the SEC which provides notice to our shareholders of a special meeting of shareholders to be held on Friday, September 29, 2017 to ratify the filing and effectiveness of the certificate of amendment to our amended and restated certificate of incorporation filed with the Secretary of State of the State of Delaware on December 3, 2015 and the 1-for-12 reverse stock split of our common stock that was effected thereby and became effective on December 3, 2015.