Long-term Debt and Capital Lease Obligations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2015	Dec. 31, 2013
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount	$ 1,138		$ 1,138
Long-term debt gross	271,164	$ 268,978	271,164
Less current installments	3,557	3,424	3,557
Long-term debt and capital lease obligations, less current installments	267,607	265,554	267,607
Second Priority Senior Secured Notes [Member]
Debt Instrument [Line Items]
Long-term debt gross	$ 245,000	245,000	$ 245,000
Fixed interest rate (in hundredths)	7.375%		7.375%
Revolver Under Credit Agreement, Variable [Member]
Debt Instrument [Line Items]
Long-term debt gross	$ 4,000	0	$ 4,000
Missouri IRBs [Member]
Debt Instrument [Line Items]
Long-term debt gross	$ 7,011	$ 7,334	$ 7,011
Fixed interest rate (in hundredths)	2.80%	2.80%	2.80%
Capital Leases [Member]
Debt Instrument [Line Items]
Long-term debt gross	$ 12,125	$ 13,288	$ 12,125
Fixed interest rate, minimum (in hundredths)			2.04%	2.04%
Fixed interest rate, maximum (in hundredths)			7.73%	7.73%
Notes Payable [Member]
Debt Instrument [Line Items]
Long-term debt gross	$ 3,028	$ 3,356	$ 3,028
Fixed interest rate, maximum (in hundredths)	2.56%	2.56%