Benefit Plans Schedule Of Percentage Of Allocation Of Plan Assets Table (Details)	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Total, percentage	100.00%
Cash and cash equivalents, percentage	0.90%	1.00%
Equity securities, percentage	43.00%	41.90%
Debt securities, percentage	46.50%	45.90%
Other investments, percentage	9.60%	11.20%
Total, percentage	100.00%	100.00%
Maximum | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Total, percentage	10.00%
Maximum | Equity securities: Equity commingled funds
Defined Benefit Plan Disclosure [Line Items]
Total, percentage	60.00%
Maximum | Debt securities: Government bonds
Defined Benefit Plan Disclosure [Line Items]
Total, percentage	100.00%
Maximum | Other investments
Defined Benefit Plan Disclosure [Line Items]
Total, percentage	100.00%
Minimum | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Total, percentage	0.00%
Minimum | Equity securities: Equity commingled funds
Defined Benefit Plan Disclosure [Line Items]
Total, percentage	0.00%
Minimum | Debt securities: Government bonds
Defined Benefit Plan Disclosure [Line Items]
Total, percentage	15.00%
Minimum | Other investments
Defined Benefit Plan Disclosure [Line Items]
Total, percentage	0.00%