Supplemental Oil And Gas Information (Narrative) (Details)	12 Months Ended
Dec. 31, 2015 $ / bbl	Dec. 31, 2014 item $ / bbl	Dec. 31, 2013 $ / bbl
Average Sales Price and Production Costs Per Unit of Production [Line Items]
Proved undeveloped reserve locations \| item		27
Barrel Of Oil [Member]
Average Sales Price and Production Costs Per Unit of Production [Line Items]
Price \| $ / bbl	43.98	88.34	90.11

The revenues derived from sales of oil or gas in each geographic area during the reporting period divided by the number of barrels of oil produced or thousands of cubic feet of gas produced.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Industry Guide
-Number 2
-Paragraph 3
-Subparagraph A

Name:	us-gaap_AverageSalesPrices
Namespace Prefix:	us-gaap_
Data Type:	us-types:perUnitItemType
Balance Type:	na
Period Type:	duration