Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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Long-Term Debt (Convertible Notes, Capital Leases) (Narrative) (Details) - USD ($)		3 Months Ended	9 Months Ended
	Jan. 21, 2016	Sep. 30, 2017	Sep. 30, 2017	Mar. 01, 2016	Aug. 31, 2011
Debt Instrument [Line Items]
Net present value of the minimum lease payments, at inception		$ 1,898,000	$ 1,898,000	$ 400,000
Amortization of capital lease assets		$ 100,000	$ 300,000
Minimum [Member]
Debt Instrument [Line Items]
Capital lease term applicable to depreciate capital assets and obligations			3 years
Maximum [Member]
Debt Instrument [Line Items]
Capital lease term applicable to depreciate capital assets and obligations			5 years
Convertible Notes [Member] \| Gorbert Inc. [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 20,000,000
Debt instrument, maturity date			Mar. 17, 2019
Aggregate principal payment required if maturity date extend to March 17, 2020	2,000,000
Aggregate principal payment required if maturity date extend to March 17, 2021	$ 2,000,000
Convertible Notes [Member] \| Gorbert Inc. [Member] \| Through and Including August 17, 2017 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	5.00%
Convertible Notes [Member] \| Gorbert Inc. [Member] \| From and After August 18, 2017 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	6.00%
Convertible Notes [Member] \| North Jackson Facility [Member]
Debt Instrument [Line Items]
Debt instrument, face amount					$ 20,000,000
Convertible Notes If Holder Elects to Convert Prior to August 17, 2017 [Member] \| Gorbert Inc. [Member]
Debt Instrument [Line Items]
Debt instrument integral multiple convertible principal amount	$ 100,000