Employee Benefit Plans (Details 3) (Postretirement Benefits Other than Pensions, USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011
Postretirement Benefits Other than Pensions
Effect of a one-percentage-point change in assumed health care cost trend rates
Effect of a 1 percentage-point increase in total of service and interest cost	$ 642
Effect of a 1 percentage-point decrease in total of service and interest cost	(355)
Effect 1 percentage-point increase in postretirement benefit obligation	6,404
Effect of a 1 percentage-point decrease in postretirement benefit obligation	(5,207)
Estimated benefit payments
2012	1,287
2013	1,445
2014	1,679
2015	1,807
2016	1,920
Years 2017-2021	$ 12,367

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The effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

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The effect of a one-percentage- point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

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The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

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The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

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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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