Employee Benefit Plan Obligations (Details 5) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011
Combined benefits expected to be paid for all Company defined benefit plans
Medicare Part D Subsidy, 2012	$ (161)
Medicare Part D Subsidy, 2013	(187)
Medicare Part D Subsidy, 2014	(209)
Medicare Part D Subsidy, 2015	(236)
Medicare Part D Subsidy, 2016	(267)
Medicare Part D Subsidy, 2017-2021	(1,903)
Expected Pension Benefit Payout [Member]
Combined benefits expected to be paid for all Company defined benefit plans
2012	3,784
2013	3,980
2014	4,346
2015	5,036
2016	5,279
2017-2021	31,164
Expected Postretirement Benefit Payout [Member]
Combined benefits expected to be paid for all Company defined benefit plans
2012	1,372
2013	1,455
2014	1,547
2015	1,638
2016	1,723
2017-2021	$ 10,040

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The amount of the aggregate benefits expected to be paid in the five fiscal years thereafter (the aggregate amount of benefits expected to be paid in years 6 through 10 after the date of the latest statement of financial position).

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The amount of the benefits expected to be paid in Year 5.

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The amount of the benefits expected to be paid in Year 4.

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The amount of the benefits expected to be paid in Year 1.

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The amount of the benefits expected to be paid in Year 3.

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The amount of the benefits expected to be paid in Year 2.

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Aggregate amount for the next five fiscal years following the first five fiscal years (that is the aggregate of fiscal years six through ten) following the balance sheet date of the prescription drug subsidy receipts expected to be received.

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Amount of the prescription drug subsidy receipts expected to be received in Year 5 after the balance sheet date.

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Amount of the prescription drug subsidy receipts expected to be received in Year 4 after the balance sheet date.

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Amount of the prescription drug subsidy receipts expected to be received in Year 1 after the balance sheet date.

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Amount of the prescription drug subsidy receipts expected to be received in Year 3 after the balance sheet date.

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Amount of the prescription drug subsidy receipts expected to be received in Year 2 after the balance sheet date.

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