Pension and Other Postretirement Benefits (Assumptions) (Details)	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Postretirement Benefit Plans Assumed Health Care Cost Trend Rates [Line Items]
Ultimate trend rate	5.00%	5.00%
Participants Age 65 And Below [Member]
Postretirement Benefit Plans Assumed Health Care Cost Trend Rates [Line Items]
Projected health care cost trend rate	8.50%	8.00%
Year ultimate trend rate is achieved	2019	2016
Participants Above Age 65 [Member]
Postretirement Benefit Plans Assumed Health Care Cost Trend Rates [Line Items]
Projected health care cost trend rate	8.50%	9.00%
Year ultimate trend rate is achieved	2019	2018
Pension Benefits [Member]
Weighted average assumptions used to determine benefit obligations at December 31:
Discount rate	4.90%	5.20%
Rate of compensation increase	3.00%	2.80%
Weighted average assumptions used to determine net periodic cost for the year ended December 31:
Discount rate	5.20%	5.70%
Expected long-term return on plan assets	6.80%	6.90%
Rate of compensation increase	2.80%	2.70%
Postretirement Benefits [Member]
Weighted average assumptions used to determine benefit obligations at December 31:
Discount rate	4.90%	5.10%
Weighted average assumptions used to determine net periodic cost for the year ended December 31:
Discount rate	5.10%	5.60%
Expected long-term return on plan assets	2.00%	2.00%

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The interest rate used to adjust for the time value of money for the plan.

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Expected rate of compensation increases (for pay-related plans).

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The interest rate used to adjust for the time value of money.

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An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

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Expected rate of compensation increases (for pay-related plans).

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The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ References

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The ultimate trend rate for health care costs.

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The year when the ultimate health care cost trend rate is expected to be reached.

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