Derivatives (Details 7) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Derivatives not designated as hedging instruments
Interest rate contracts included in other assets	$ 23	$ 31
Interest rate contracts included in other long term liabilities	(592)	(372)
Total fair value of interest rate derivatives not designated as hedging instruments	(569)	(341)
Derivatives designated as hedging instruments
Interest rate contract included in other long term liabilities	(1,540)	(1,856)
Total fair value of interest rate derivatives designated as hedging instruments	$ (1,540)	$ (1,856)

Fair value as of the balance sheet date of all derivative assets not designated as hedging instruments.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 17

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(2)

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Fair value as of the balance sheet date of all derivatives not designated as hedging instruments.

+ References

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

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-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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

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-Paragraph 17

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