Employee Benefit Plans (Defined Benefit Plan Assumptions Used) (Details)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Assumed rates of return on invested assets	6.00%	6.00%	6.50%
Pension Benefits | Minimum
Defined Benefit Plan Disclosure [Line Items]
Discount rates — benefit obligation	3.60%	3.75%	2.75%
Discount rates — service cost	3.75%	2.75%	3.00%
Pension Benefits | Maximum
Defined Benefit Plan Disclosure [Line Items]
Discount rates — benefit obligation	4.20%	4.50%	4.00%
Discount rates — service cost	4.50%	4.25%	4.75%
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Discount rates — benefit obligation	4.40%	4.75%	4.25%
Discount rates — service cost	4.75%	4.25%	5.00%
Assumed rates of return on invested assets	0.00%	0.00%	0.00%
Salary increase assumptions	3.00%	3.00%	3.00%