Long-Term Debt (Details1) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011
Maturities of long-term debt outstanding
2012	$ 738
2013	680
2014	279
2015	33
2016	3
Thereafter	259,675
Revolving Credit Agreement [Member]
Maturities of long-term debt outstanding
2012	0
2013	0
2014	0
2015	0
2016	0
Thereafter	120,906
Senior Notes [Member]
Maturities of long-term debt outstanding
2012	0
2013	0
2014	0
2015	0
2016	0
Thereafter	125,000
Industrial revenue bond and other notes payable [Member]
Maturities of long-term debt outstanding
2012	738
2013	680
2014	279
2015	33
2016	3
Thereafter	$ 13,769

Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 47

-Paragraph 10

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year.

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