Commitments and Contingencies (Helium Supply Arrangement) (Details) $ in Millions	9 Months Ended
Sep. 30, 2019 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Term of long term supply arrangement	20 years
Maximum annual payment in event of shortfall	$ 8.0
Maximum payment in event of shortfall	$ 46.0

Maximum amount over the term of the contract that can be paid in the event of a shortfall in volume on a supply commitment.

No definition available.

Name:	dnr_MaximumPaymentInEventOfShortfall
Namespace Prefix:	dnr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration