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Investment in American Shale Oil, LLC (Details Textual) $ in Millions |  |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Feb. 23, 2016 USD ($) | Mar. 31, 2009 USD ($) | Jan. 31, 2014 USD ($) | Dec. 31, 2015 USD ($) a
Minimum [Member] | Subsequent Event [Member] |  |  |  |
Schedule of investment (Textual) |  |  |  |
Remediation and reclamation costs |  |  |  |
Maximum [Member] | Subsequent Event [Member] |  |  |  |
Schedule of investment (Textual) |  |  |  |
Remediation and reclamation costs | $ 2.0 |  |  |
AMSO, LLC [Member] |  |  |  |
Schedule of investment (Textual) |  |  |  |
Area of land awarded for lease | a |  |  |  | 160
Lease expiration period |  |  |  | 10 years
Extension period of lease |  |  |  | 5 years
Area of land subject to commercial lease | a |  |  |  | 5,120
Ownership interest of company in AMSO, LLC |  |  |  | 50.00%
Percentage of initial expenditure funded by holding company |  |  |  | 20.00%
Initial expenditures |  |  |  | $ 50.0
Percentage of funding provided by holding company for next increased expenditures |  |  |  | 35.00%
Amount of expenditures to be funded 35% by holding company |  |  |  | $ 50.0
Expenditures in excess of this amount to be funded 50% by holding company |  |  |  | $ 100.0
Percentage of funding to AMSO, LLC's for converting research, development and demonstration lease to a commercial lease |  |  |  | 40.00%
Cumulative contributions of AMSO and Total to AMSO, LLC |  |  |  | $ 82.9
Aggregate amount of expenditures to be funded 38% by holding company |  |  |  | $ 0.3
Percentage of holding company share of required funding paid |  |  |  | 28.00%
New equity method investment ownership percentage after dilution |  |  |  | 41.30%
Expenditures in excess of this amount to be funded by holding company dilution percentage |  |  |  | $ 100.0
New percentage of funding for approved expenditures in excess of $100 million |  |  |  | 28.90%
Amount of expenditures allocated to holding company after dilution |  |  | $ 12.1 |
TOTAL S.A. [Member] |  |  |  |
Schedule of investment (Textual) |  |  |  |
Ownership interest of company in AMSO, LLC |  | 50.00% |  | 50.00%
Capital contributions to AMSO, LLC |  | $ 3.2 |  |
Description of ownership exchange transaction |  | All owners of equity interests in AMSO, LLC other than AMSO exchanged their ownership interest for a proportionate share of a 1% override on AMSO, LLC's future revenue. |  |
Amount of expenditures funded by holding company |  |  |  | $ 4.6
New equity method investment ownership percentage after dilution |  |  |  | 58.70%
New percentage of funding for approved expenditures in excess of $100 million |  |  |  | 71.10%

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