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Long-Term Debt (Notes, Capital Leases) (Narrative) (Details) - USD ($)			12 Months Ended
	Mar. 30, 2018	Jan. 21, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2011
Debt Instrument [Line Items]
Aggregate principal payment required if maturity date extend to March 17, 2020			$ 1,429,000
Aggregate principal payment required if maturity date extend to March 17, 2021			22,131,000
Net present value of the minimum lease payments, at inception			1,502,000	$ 500,000
Amortization of capital lease assets			$ 500,000	$ 400,000
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
Notes [Member] \| Gorbert Inc. [Member]
Debt Instrument [Line Items]
Debt instrument, face amount		$ 20,000,000
Debt instrument, maturity date	Mar. 17, 2020	Mar. 17, 2019
Aggregate principal payment required if maturity date extend to March 17, 2020	$ 2,000,000
Current portion of long-term debt	$ 2,000,000
Notes [Member] \| Through and Including August 17, 2017 [Member] \| Gorbert Inc. [Member]
Debt Instrument [Line Items]
Debt instrument interest rate		5.00%
Notes [Member] \| From and After August 18, 2017 [Member] \| Gorbert Inc. [Member]
Debt Instrument [Line Items]
Debt instrument interest rate		6.00%
Notes [Member] \| North Jackson Facility [Member]
Debt Instrument [Line Items]
Debt instrument, face amount					$ 20,000,000