Debt Short-term and Long-term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2016	May 19, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Line of Credit Facility, Amount Outstanding	$ 0		$ 66,100
Other Long-term Debt, Primarily Capital Leases	96		428
Plus: derivative liability for embedded conversion option	403	$ 11,574	0
Less: unamortized discount	(7,587)		(12,255)
Less: unamortized debt issuance costs	(5,199)		(4,147)
Less: current portion	137		7,012
Total long-term portion	286,459		310,614
Long-term Debt	286,596		317,626
Senior Secured Notes Due in 2018 [Member]
Debt Instrument [Line Items]
Senior Notes	177,019		203,319
Senior Secured Notes Due in 2016 [Member]
Debt Instrument [Line Items]
Senior Notes	0		6,681
Convertible Notes Due in 2017 [Member]
Debt Instrument [Line Items]
Convertible Debt	41		57,500
Senior Secured Term Loan Credit Facilities [Member]
Debt Instrument [Line Items]
Loans Payable	99,500		0
Convertible Notes Due in 2019 [Member]
Debt Instrument [Line Items]
Convertible Debt	$ 22,323		$ 0

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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt discount.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt and capital leases due within one year or the normal 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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Amount of long-term debt classified as other.

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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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