Schedule of Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Convertible Debt, Current	$ 3,314	$ 0
Secured note	0	250
Wyoming Industrial Development Revenue Bond Loan Current	3,133	3,291
Finance leases and other Current	18	41
Total current loans and borrowings	6,465	3,582
Convertible debentures	13,256	14,624
Secured note	0	224
Wyoming Industrial Development Revenue Bond Loan Noncurrent	12,489	14,078
Finance leases and other Noncurrent	0	11
Total long-term loans and borrowings	$ 25,745	$ 28,937

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying value as of the balance sheet date of the portion of long-term, collateralized debt obligations due within one year or the operating cycle, if longer. Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets.

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