Employee and Retiree Benefit Plans (Weighted-Average Assumptions used in Measurement of Benefit Obligations and Net Periodic Benefit Expense) (Details)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets	6.11%
Expected return on plan assets	6.11%
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit Obligation, Discount rate	3.94%	4.78%
Expected return on plan assets	6.11%	6.24%
Benefit Obligation, Rate of compensation increase	3.69%	4.14%
Net periodic benefit expense, Discount rate	4.56%	4.23%
Expected return on plan assets	6.11%	6.24%
Net periodic benefit expense, Rate of compensation increase	3.69%	4.12%
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit Obligation, Discount rate	4.12%	4.91%
Net periodic benefit expense, Discount rate	4.91%	4.18%