Commitments And Contingencies (Narrative) (Details) $ in Thousands	3 Months Ended
	Jun. 30, 2019 USD ($)	Mar. 31, 2018 USD ($)	Mar. 31, 2018 CAD ($)	Sep. 30, 2020 USD ($)
Loss Contingencies [Line Items]
Preliminary tax assessment		$ 923,000	$ 1,218
Maximum [Member] | U.S. Employee [Member]
Loss Contingencies [Line Items]
Interest and penalties	$ 300,000
Accrual related to settlement				$ 300,000
Minimum [Member] | U.S. Employee [Member]
Loss Contingencies [Line Items]
Interest and penalties	$ 200,000