Subsequent Events	3 Months Ended
Mar. 31, 2013
Subsequent Events [Abstract]
Subsequent Events	13. Subsequent Events The Company has evaluated subsequent events and transactions through the date of this filing for potential recognition or disclosure in the financial statements and has noted no other subsequent events requiring recognition or disclosure other than as stated below. On May 8, 2013, the Company entered into a Securities Purchase Agreement (the “Purchase Agreement”) with Air Liquide Investissements d'Avenir et de Demonstration (“Air Liquide”), pursuant to which the Company agreed to issue and sell to Air Liquide approximately 10,500 shares of the Company’s Series C Redeemable Convertible Preferred Stock, par value $0.01 per share (the “Series C Preferred Stock”), for an aggregate purchase price of approximately $2.6 million (Euro 2 million) in cash. On an as-converted basis, Air Liquide is expected to initially own approximately 14% of the Company’s outstanding common stock, par value $0.01 per share (the “Common Stock”). The transaction contemplated by the Securities Purchase Agreement is expected to close during the week of May 13, 2013 and no later than May 22, 2013. Under the terms of the Purchase Agreement, for so long as Air Liquide holds any shares of Series C Preferred Stock, Air Liquide shall be entitled to designate one director to the Company’s Board of Directors. In the event the Series C Preferred Stock is converted into shares of Common Stock and Air Liquide continues to hold at least 5% of the outstanding shares of Common Stock or 50% of the shares of Common Stock held by Air Liquide on an as-converted basis immediately following the issuance of the Series C Preferred Stock, Air Liquide shall continue to be entitled to designate one director to the Company’s Board of Directors. The Purchase Agreement also provides Air Liquide with the right to participate in certain future equity financings by the Company. The Series C Preferred Stock will rank senior to the Common Stock with respect to rights upon the liquidation, dissolution or winding up of the Company. The Series C Preferred Stock will be entitled to receive dividends at a rate of 8% per annum payable in equal quarterly installments in cash or in shares of Common Stock, at the Company’s option. The Series C Preferred Stock will be convertible into shares of Common Stock, at a conversion price equal to $0.248794 per share, at Air Liquide’s option, (1) on or after May 8, 2014 or (2) upon any liquidation, dissolution or winding up of the Company, any sale, consolidation or merger of the Company resulting in a change of control, or any sale or other transfer of all or substantially all of the assets of the Company. The Series C Preferred Stock will have customary redemption rights and weighted average anti-dilution protection. The Series C Preferred Stock will vote together with the Common Stock on an as-converted basis on all matters. The shares of Series C Preferred Stock were issued in a private placement exempt from registration pursuant to Section 4(2) of the Securities Act of 1933, as amended (the “Securities Act”). In connection with the Series C Preferred Stock investment, the Company and Axane, S.A. (“Axane”), a subsidiary of Air Liquide S.A., entered into transactions related to their HyPulsion S.A.S. joint venture. HyPulsion was formed by the Company and Axane to develop and market hydrogen fuel cell systems for the European material handling market. Axane purchased a 25% ownership interest in HyPulsion from the Company for a cash purchase price of $3.3 million (Euro 2.5 million). The Company now owns 20% and Axane owns 80% of HyPulsion. The Company has the right to purchase 60% of HyPulsion from Axane in 2018 at a formula price. If the Company does not exercise its purchase right, Axane has the right to buy the Company’s remaining 20% interest at a formula price. The Company and HyPulsion also entered into an engineering service agreement under which, among other things, the Company will provide HyPulsion with engineering and technical services for a new fuel cell assembly line and manufacturing execution system. Under the service agreement, HyPulsion has paid the Company approximately $659,000 (Euro 500,000) in the aggregate for services to be performed by the Company.

Subsequent Events

3 Months Ended

Mar. 31, 2013

13. Subsequent Events

The Company has evaluated subsequent events and transactions through the date of this filing for potential recognition or disclosure in the financial statements and has noted no other subsequent events requiring recognition or disclosure other than as stated below.

On May 8, 2013, the Company entered into a Securities Purchase Agreement (the “Purchase Agreement”) with Air Liquide Investissements d'Avenir et de Demonstration (“Air Liquide”), pursuant to which the Company agreed to issue and sell to Air Liquide approximately 10,500 shares of the Company’s Series C Redeemable Convertible Preferred Stock, par value $0.01 per share (the “Series C Preferred Stock”), for an aggregate purchase price of approximately $2.6 million (Euro 2 million) in cash. On an as-converted basis, Air Liquide is expected to initially own approximately 14% of the Company’s outstanding common stock, par value $0.01 per share (the “Common Stock”). The transaction contemplated by the Securities Purchase Agreement is expected to close during the week of May 13, 2013 and no later than May 22, 2013.

Under the terms of the Purchase Agreement, for so long as Air Liquide holds any shares of Series C Preferred Stock, Air Liquide shall be entitled to designate one director to the Company’s Board of Directors. In the event the Series C Preferred Stock is converted into shares of Common Stock and Air Liquide continues to hold at least 5% of the outstanding shares of Common Stock or 50% of the shares of Common Stock held by Air Liquide on an as-converted basis immediately following the issuance of the Series C Preferred Stock, Air Liquide shall continue to be entitled to designate one director to the Company’s Board of Directors. The Purchase Agreement also provides Air Liquide with the right to participate in certain future equity financings by the Company.

The Series C Preferred Stock will rank senior to the Common Stock with respect to rights upon the liquidation, dissolution or winding up of the Company. The Series C Preferred Stock will be entitled to receive dividends at a rate of 8% per annum payable in equal quarterly installments in cash or in shares of Common Stock, at the Company’s option. The Series C Preferred Stock will be convertible into shares of Common Stock, at a conversion price equal to $0.248794 per share, at Air Liquide’s option, (1) on or after May 8, 2014 or (2) upon any liquidation, dissolution or winding up of the Company, any sale, consolidation or merger of the Company resulting in a change of control, or any sale or other transfer of all or substantially all of the assets of the Company. The Series C Preferred Stock will have customary redemption rights and weighted average anti-dilution protection. The Series C Preferred Stock will vote together with the Common Stock on an as-converted basis on all matters.

The shares of Series C Preferred Stock were issued in a private placement exempt from registration pursuant to Section 4(2) of the Securities Act of 1933, as amended (the “Securities Act”).

In connection with the Series C Preferred Stock investment, the Company and Axane, S.A. (“Axane”), a subsidiary of Air Liquide S.A., entered into transactions related to their HyPulsion S.A.S. joint venture. HyPulsion was formed by the Company and Axane to develop and market hydrogen fuel cell systems for the European material handling market. Axane purchased a 25% ownership interest in HyPulsion from the Company for a cash purchase price of $3.3 million (Euro 2.5 million). The Company now owns 20% and Axane owns 80% of HyPulsion. The Company has the right to purchase 60% of HyPulsion from Axane in 2018 at a formula price. If the Company does not exercise its purchase right, Axane has the right to buy the Company’s remaining 20% interest at a formula price.

The Company and HyPulsion also entered into an engineering service agreement under which, among other things, the Company will provide HyPulsion with engineering and technical services for a new fuel cell assembly line and manufacturing execution system. Under the service agreement, HyPulsion has paid the Company approximately $659,000 (Euro 500,000) in the aggregate for services to be performed by the Company.