Fair Value Measurements (Details Textual) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($) shares
Fair Value Measurements (Textual)
Asset retirement obligation, description	The estimated timing of reclamation ranging from one to 75 years based on estimates from reserve engineers; an inflation rate between 1.52% to 2.79%; and a credit adjusted risk-free rate between 3.28% to 8.27%, which takes into account our credit risk and the time value of money. Given the unobservable nature of the inputs, the initial measurement of the asset retirement obligation liability is deemed to use Level 3 inputs (see Note 3). During the three month period ended March 31, 2019, we did not record any additions to asset retirement obligations.
Minimum [Member]
Fair Value Measurements (Textual)
Fair value of debt discount Issuance | shares	585
Maximum [Member]
Fair Value Measurements (Textual)
Fair value of debt discount Issuance | shares	1,425
Class A Units [Member]
Fair Value Measurements (Textual)
Fair value of debt discount	$ 1
Class A Units [Member] | Subordinated Notes [Member]
Fair Value Measurements (Textual)
Fair value of debt discount	1,300
Class A Units [Member] | Subordinated Notes [Member]
Fair Value Measurements (Textual)
Fair value of debt discount	490
Class A Units [Member] | California Warrant [Member | Minimum [Member]
Fair Value Measurements (Textual)
Fair value of warrant	20
Class A Units [Member] | California Warrant [Member | Maximum [Member]
Fair Value Measurements (Textual)
Fair value of warrant	$ 45