Debt - Parentheticals (Details)			12 Months Ended
Dec. 31, 2012 Line Of Credit [Member]	Dec. 31, 2011 Line Of Credit [Member]	Dec. 31, 2012 Montgomery County Industrial Development Authority Bond [Member]	Dec. 31, 2012 Butler County Port Authority Bond [Member]
Debt Instrument [Line Items]
Debt Instrument Interest Rate Stated Percentage			5.60%	5.26%
Long-term Debt, Weighted Average Interest Rate	1.96%	2.06%
Debt Instrument Maturity Year			2018	2028

Interest rate stated in the contractual debt agreement.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: 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(a)(1))

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

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