Derivatives (Details Textual) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2012	Jun. 12, 2009
Derivatives (Textual) [Abstract]
Hedged value of revolving credit facility	$ 100
Variable Interest Rate Swap Expiration Date	Oct. 12, 2012
Variable portion of the interest rate swap tied	1-Month LIBOR
Commodity Futures Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivatives scheduled to mature	February 2014
Cash flow hedge derivative gains (losses) expected to be reclassified into earnings within the next 12 months	1.9
Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount of Interest rate risk hedge		100
Variable interest rate swap with financial institution at fixed interest rate		2.66%
Notional amount cash flow Hedge	100
Cash flow hedge derivative gains (losses) expected to be reclassified into earnings within the next 12 months	$ (0.1)

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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- Definition

Hedged value of revolving credit facility.

+ References

No definition available.

+ Details

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- Definition

Maximum length of time hedged in cash flow hedge.

+ References

No definition available.

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- Definition

Variable interest rate swap expiration date.

+ References

No definition available.

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7668309&loc=d3e80748-113994

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 45

-Subparagraph b(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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- Definition

The reference rate for the variable rate of the interest rate derivative, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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- Definition

Aggregate notional amount of all derivatives designated as cash flow hedging instruments. The notional amount relates to a number of currency units, shares, bushels, pounds, or other units specified in a derivative instrument.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

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