Employee Benefit Plans Defined Benefit Plan Assumptions Used (Details)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rates - benefit obligation			5.25%
Discount rates — service cost		5.25%	5.75%
Assumed rates of return on invested assets	7.00%	7.00%	7.00%
Pension Plans [Member] | Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rates - benefit obligation	2.25%	3.75%
Discount rates — service cost	3.75%
Pension Plans [Member] | Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rates - benefit obligation	4.00%	4.75%
Discount rates — service cost	4.75%
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rates - benefit obligation	4.25%	5.00%	5.25%
Discount rates — service cost	5.00%	5.25%	5.75%
Assumed rates of return on invested assets	0.00%	0.00%	0.00%
Salary increase assumptions	3.00%	3.00%	3.00%