Summary of Significant Accounting Policies (Summary Of Other Intangible Assets) (Details) - Other intangible assets	12 Months Ended
	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Weighted Average Life	14 years
Minimum
Finite-Lived Intangible Assets [Line Items]
Useful Life Range	5 years
Maximum
Finite-Lived Intangible Assets [Line Items]
Useful Life Range	20 years