Derivative Instruments and Hedging Activities (Details Textuals) (USD $)	Sep. 30, 2012
Derivative Instruments and Hedging Activities (Textuals) [Abstract]
Derivative Weighted Average Floor Price Restructured Collars	$ 80

The weighted average floor price of derivatives restructured in the current period.

No definition available.

Name:	dnr_DerivativeWeightedAverageFloorPriceRestructuredCollars
Namespace Prefix:	dnr_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant