Employee Benefit Plans (Allocation of Plan Assets) (Details)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Pension Benefits
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation	100.00%
Actual plan asset allocation	100.00%	100.00%
Postretirement Benefits
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation	100.00%
Actual plan asset allocation	100.00%	100.00%
Equity securities | Pension Benefits
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation	0.00%
Actual plan asset allocation	0.00%	0.00%
Equity securities | Postretirement Benefits
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation	56.00%
Actual plan asset allocation	56.00%	60.00%
Debt securities | Pension Benefits
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation	0.00%
Actual plan asset allocation	0.00%	0.00%
Debt securities | Postretirement Benefits
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation	44.00%
Actual plan asset allocation	44.00%	40.00%
Cash and cash equivalents | Pension Benefits
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation	100.00%
Actual plan asset allocation	100.00%	100.00%
Cash and cash equivalents | Postretirement Benefits
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation	0.00%
Actual plan asset allocation	0.00%	0.00%