Asset Retirement Obligation - Narrative (Details)	3 Months Ended
Mar. 31, 2024
Asset Retirement Obligation [Abstract]
Current year inflation (as a percent)	2.50%
Change in net present value (as a percent)	7.50%

The percentage by which the liability is increased annually for the change in its present value.

No definition available.

Name:	rsrv_AssetRetirementObligationChangeInPresentValuePercent
Namespace Prefix:	rsrv_
Data Type:	dtr-types1:percentItemType
Balance Type:	na
Period Type:	duration