Subsequent events (Details) (USD $)	Feb. 20, 2014 Senior Convertible Notes Due 2017 Bruno Meier Subsequent Event	Feb. 20, 2014 Senior Convertible Notes Due 2017 Joan Giacinti Subsequent Event	Feb. 20, 2014 Senior Convertible Notes Due 2017 Charles T. Maxwell Subsequent Event	Feb. 20, 2014 Senior Convertible Notes Due 2017 Nettlestone Enterprises Limited Subsequent Event	Jun. 14, 2013 Unsecured Debt Senior Unsecured Convertible Notes Due 2015	Feb. 20, 2014 Convertible Debt Senior Convertible Notes Due 2017 Subsequent Event	Dec. 31, 2013 EuroSite Power	Jun. 14, 2013 EuroSite Power Senior Unsecured Convertible Notes Due 2015	Jun. 14, 2013 EuroSite Power Senior Unsecured Convertible Notes Due 2015 Bruno Meier	Jun. 14, 2013 EuroSite Power Senior Unsecured Convertible Notes Due 2015 Joan Giacinti	Jun. 14, 2013 EuroSite Power Senior Unsecured Convertible Notes Due 2015 Charles T. Maxwell	Jun. 14, 2013 EuroSite Power Senior Unsecured Convertible Notes Due 2015 Nettlestone Enterprises Limited	Feb. 20, 2014 EuroSite Power Senior Convertible Notes Due 2017 Subsequent Event	Feb. 20, 2014 EuroSite Power Senior Convertible Notes Due 2017 Bruno Meier Subsequent Event	Feb. 20, 2014 EuroSite Power Senior Convertible Notes Due 2017 Joan Giacinti Subsequent Event	Feb. 20, 2014 EuroSite Power Senior Convertible Notes Due 2017 Charles T. Maxwell Subsequent Event	Feb. 20, 2014 EuroSite Power Senior Convertible Notes Due 2017 Nettlestone Enterprises Limited Subsequent Event	Feb. 20, 2014 EuroSite Power Senior Convertible Notes Due 2017 Perastra Management Management S.A Subsequent Event	Feb. 20, 2014 EuroSite Power Senior Convertible Notes Due 2017 Yves Micheli Subsequent Event	Jun. 14, 2013 EuroSite Power Unsecured Debt Senior Unsecured Convertible Notes Due 2015	Feb. 20, 2014 EuroSite Power Convertible Debt Senior Convertible Notes Due 2017 Subsequent Event
Subsequent Event [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					4.00%	4.00%		6.00%												4.00%	4.00%
Line of Credit Facility, Maximum Borrowing Capacity	$ 250,000	$ 300,000	$ 250,000	$ 300,000			$ 1,100,000	$ 1,100,000	$ 250,000	$ 300,000	$ 250,000	$ 300,000	$ 1,100,000	$ 250,000	$ 300,000	$ 250,000	$ 300,000	$ 1,500,000	$ 300,000
Debt Instrument, Face Amount						$ 4,000,000														$ 4,000,000	$ 4,000,000
Debt Instrument, Convertible, Shares						1,667														1,000	1,667