Employee Postretirement Benefits (Weighted-Average Assumptions) (Details)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Other Postretirement Benefit Plans, Defined Benefit [Member]
Net cost, discount rate	5.44%	5.79%	6.50%
Net cost, expected long-term return on plan assets	0.00%	0.00%	0.00%
Net cost, rate of compensation increase	0.00%	0.00%	0.00%
Benefit obligations, discount rate	4.70%	5.44%
Benefit obligations, rate of compensation increase	0.00%	0.00%
Defined Benefit Pension [Member]
Net cost, discount rate	5.51%	5.85%	6.40%
Net cost, expected long-term return on plan assets	7.14%	7.96%	8.17%
Net cost, rate of compensation increase	4.05%	4.09%	3.94%
Benefit obligations, discount rate	4.87%	5.51%
Benefit obligations, rate of compensation increase	2.91%	4.05%