Long-Term Debt And Lease Liabilities (Components Of Lease Cost) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019
Lease Cost [Line Items]
Total operating lease cost	$ 15	$ 47
Amortization of right of use assets	21	62
Interest on lease liabilities	1	4
Total finance lease cost	22	66
Production Costs And Taxes [Member]
Lease Cost [Line Items]
Total operating lease cost	3	10
General and Administrative [Member]
Lease Cost [Line Items]
Total operating lease cost	$ 12	$ 37