Employee Benefit Plans Assumptions Used in Calculations (Details)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	4.20%	5.25%	5.80%
Rate of compensation increase	4.50%	4.50%	4.50%
Discount rate methodology	closely approximates interest rates on high quality, long-term obligations
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	5.25%	5.80%	6.15%
Expected long-term return on plan assets	8.50%	8.50%	8.50%
Rate of compensation increase	4.50%	4.50%	4.50%
Return on plan assets methodology	based on historical and expected long-term rates of return on broad equity and bond indices and consideration of the actual annualized rate of return
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	4.10%	5.10%	5.50%
Rate of compensation increase	4.50%	4.50%	4.50%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	5.10%	5.50%	6.15%
Expected long-term return on plan assets	0.00%	0.00%	0.00%
Rate of compensation increase	4.50%	4.50%	4.50%