Employee Benefit Plans (Details 5)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Pension Benefits [Member]
Assumptions used in the measurement of net periodic cost
Discount rate	4.64%	3.70%	4.25%
Expected return on plan assets	7.50%	7.50%	7.50%
Postretirement Benefits [Member]
Assumptions used in the measurement of net periodic cost
Discount rate	4.39%	3.67%	4.18%