Significant Accounting Policies (Estimated Lives of Prperty, Plant and Equipment) (Details)	12 Months Ended
	Dec. 31, 2020
Minimum [Member] | Buildings [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	20 years
Minimum [Member] | Machinery and Equipment [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Maximum [Member] | Buildings [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	40 years
Maximum [Member] | Machinery and Equipment [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	15 years