Long-Term Debt - Components of Long-Term Debt and Capital Leases (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Long-term debt and capital lease	$ 531,745	$ 535,711
Less-current maturities of long-term debt	1,306	1,656
Non current portion of long term debt and capital lease obligation	530,439	534,055
Senior Secured Asset Based Revolving Credit Facility, Due 2020 [Member]
Debt Instrument [Line Items]
Long-term debt and capital lease	62,900
Senior Secured Revolving Credit Facility, Due 2016 [Member]
Debt Instrument [Line Items]
Long-term debt and capital lease		131,300
Revenue Bonds Series 2014 Due December 2044 [Member]
Debt Instrument [Line Items]
Long-term debt and capital lease	25,000	25,000
Revenue Bonds Series 2005R-2, Due January 2025 [Member]
Debt Instrument [Line Items]
Long-term debt and capital lease	21,400	21,400
Revenue Bonds Series 2015 Due August 2035 [Member]
Debt Instrument [Line Items]
Long-term debt and capital lease	15,000
Long-Term Revenue Bonds Series 2013 Due April 2036 [Member]
Debt Instrument [Line Items]
Long-term debt and capital lease	16,000	16,000
Revenue Bonds Series 2013 Due April 2029 [Member]
Debt Instrument [Line Items]
Long-term debt and capital lease	11,000	11,000
Revenue Bonds Series, 2005R-1, Due January 2025 [Member]
Debt Instrument [Line Items]
Long-term debt and capital lease	3,600	3,600
Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Long-term debt and capital lease	2,784	3,295
Notes Payable [Member]
Debt Instrument [Line Items]
Long-term debt and capital lease	247	435
Senior Subordinated Notes Due 2019 Notes [Member]
Debt Instrument [Line Items]
Long-term debt and capital lease	$ 373,814	$ 323,681

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13,16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section H

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