Employee Benefit Plan Obligations (Details 1) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Amounts recognized in the consolidated balance sheets
Employee benefit plan obligations	$ (52,972)	$ (30,152)
Pension Benefits [Member]
Amounts recognized in the consolidated balance sheets
Accrued expenses	(213)	(210)
Employee benefit plan obligations	(22,158)	(6,296)
Net amount recognized	(22,371)	(6,506)
Postretirement Benefits [Member]
Amounts recognized in the consolidated balance sheets
Accrued expenses	(1,211)	(1,196)
Employee benefit plan obligations	(30,347)	(23,397)
Net amount recognized	$ (31,558)	$ (24,593)

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For a classified balance sheet, the amount recognized in balance sheet as a current liability associated with an underfunded defined benefit plan.

+ References

+ Details

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- Definition

This represents the entire liability recognized in the balance sheet that is associated with the defined benefit plans.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph c

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 6

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 3

+ Details

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- Definition

This represents the noncurrent liability for underfunded plans recognized in the balance sheet that is associated with the defined benefit pension plans and other postretirement defined benefit plans.

+ References

+ Details

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