Oil And Gas Properties (Schedule Of Oil And Gas Properties) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Oil And Gas Properties [Abstract]
Oil and gas properties	$ 6,528	$ 6,503
Unevaluated properties		23
Accumulated depreciation, depletion and amortization	(1,878)	(1,722)
Oil and gas properties	$ 4,650	$ 4,804

Oil and gas properties, net of depletion, carried under the full cost method.

No definition available.

Name:	us-gaap_OilAndGasPropertyFullCostMethodNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant