Employee Benefits (Target Allocations - Other Postretirment Benefit Plans) (Details) - Other Postretirement Benefit Plan	12 Months Ended
	Dec. 31, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Assets, Target Allocations Total	100.00%
Equity Securities
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	45.40%
Fixed Income
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	39.30%
Alternative Investments
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	15.30%
Alternative Investment-Equity fund - Global equity
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Alternative Investment-Equity Fund Allocation	75.00%
Alternative Investment-Equity fund - Marketable real assets
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Alternative Investment-Equity Fund Allocation	15.00%
Alternative Investment-Equity fund - Global fixed income
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Alternative Investment-Equity Fund Allocation	10.00%