Employee Benefit Plans (Pension Plan's Weighted-average Asset Allocations) (Details)	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan, Information about Plan Assets [Abstract]
Weighted average asset allocations	100.00%	100.00%
U.S. Equity [Member]
Defined Benefit Plan, Information about Plan Assets [Abstract]
Weighted average asset allocations	27.00%	27.10%
International Equity [Member]
Defined Benefit Plan, Information about Plan Assets [Abstract]
Weighted average asset allocations	18.50%	17.70%
Fixed Income [Member]
Defined Benefit Plan, Information about Plan Assets [Abstract]
Weighted average asset allocations	52.50%	53.80%
Money Market
Defined Benefit Plan, Information about Plan Assets [Abstract]
Weighted average asset allocations	2.00%	1.40%