Debt Short-term and Long-term Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	May 19, 2016
Debt Instrument [Line Items]
Other Long-term Debt, Primarily Capital Leases	$ 50	$ 96
Plus: derivative liability for embedded conversion option	549	403	$ 11,574
Less: unamortized discount	(6,852)	(7,587)
Less: unamortized debt issuance costs	(5,438)	(5,199)
Less: current portion	75	137
Total long-term portion	287,101	286,459
Long-term Debt	287,176	286,596
Senior Secured Notes Due in 2018 [Member]
Debt Instrument [Line Items]
Senior Notes	177,019	177,019
Convertible Notes Due in 2017 [Member]
Debt Instrument [Line Items]
Convertible Debt	25	41
Senior Secured Term Loan Credit Facilities [Member]
Debt Instrument [Line Items]
Loans Payable	99,500	99,500
Convertible Notes Due in 2019 [Member]
Debt Instrument [Line Items]
Convertible Debt	$ 22,323	$ 22,323

Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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Including the current and noncurrent portions, aggregate carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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